Add UnregisteredRecipientException

2025-12-26 02:24:21 +01:00 · 2021-12-30 17:15:40 +01:00
parent a7ecb9e10f
commit c88c92086e
20 changed files with 244 additions and 117 deletions
--- a/lib/src/main/java/org/asamk/signal/manager/Manager.java
+++ b/lib/src/main/java/org/asamk/signal/manager/Manager.java
@@ -13,6 +13,7 @@ import org.asamk.signal.manager.api.RecipientIdentifier;
 import org.asamk.signal.manager.api.SendGroupMessageResults;
 import org.asamk.signal.manager.api.SendMessageResults;
 import org.asamk.signal.manager.api.TypingAction;
+import org.asamk.signal.manager.api.UnregisteredRecipientException;
 import org.asamk.signal.manager.api.UpdateGroup;
 import org.asamk.signal.manager.config.ServiceConfig;
 import org.asamk.signal.manager.config.ServiceEnvironment;
@@ -40,7 +41,6 @@ import java.util.Map;
 import java.util.Optional;
 import java.util.Set;
 import java.util.UUID;
-import java.util.concurrent.TimeUnit;

 public interface Manager extends Closeable {

@@ -123,23 +123,23 @@ public interface Manager extends Closeable {

    void setRegistrationLockPin(Optional<String> pin) throws IOException;

-    Profile getRecipientProfile(RecipientIdentifier.Single recipient) throws IOException;
+    Profile getRecipientProfile(RecipientIdentifier.Single recipient) throws IOException, UnregisteredRecipientException;

    List<Group> getGroups();

    SendGroupMessageResults quitGroup(
            GroupId groupId, Set<RecipientIdentifier.Single> groupAdmins
-    ) throws GroupNotFoundException, IOException, NotAGroupMemberException, LastGroupAdminException;
+    ) throws GroupNotFoundException, IOException, NotAGroupMemberException, LastGroupAdminException, UnregisteredRecipientException;

    void deleteGroup(GroupId groupId) throws IOException;

    Pair<GroupId, SendGroupMessageResults> createGroup(
            String name, Set<RecipientIdentifier.Single> members, File avatarFile
-    ) throws IOException, AttachmentInvalidException;
+    ) throws IOException, AttachmentInvalidException, UnregisteredRecipientException;

    SendGroupMessageResults updateGroup(
            final GroupId groupId, final UpdateGroup updateGroup
-    ) throws IOException, GroupNotFoundException, AttachmentInvalidException, NotAGroupMemberException, GroupSendingNotAllowedException;
+    ) throws IOException, GroupNotFoundException, AttachmentInvalidException, NotAGroupMemberException, GroupSendingNotAllowedException, UnregisteredRecipientException;

    Pair<GroupId, SendGroupMessageResults> joinGroup(
            GroupInviteLinkUrl inviteLinkUrl
@@ -159,7 +159,7 @@ public interface Manager extends Closeable {

    SendMessageResults sendMessage(
            Message message, Set<RecipientIdentifier> recipients
-    ) throws IOException, AttachmentInvalidException, NotAGroupMemberException, GroupNotFoundException, GroupSendingNotAllowedException;
+    ) throws IOException, AttachmentInvalidException, NotAGroupMemberException, GroupNotFoundException, GroupSendingNotAllowedException, UnregisteredRecipientException;

    SendMessageResults sendRemoteDeleteMessage(
            long targetSentTimestamp, Set<RecipientIdentifier> recipients
@@ -171,21 +171,21 @@ public interface Manager extends Closeable {
            RecipientIdentifier.Single targetAuthor,
            long targetSentTimestamp,
            Set<RecipientIdentifier> recipients
-    ) throws IOException, NotAGroupMemberException, GroupNotFoundException, GroupSendingNotAllowedException;
+    ) throws IOException, NotAGroupMemberException, GroupNotFoundException, GroupSendingNotAllowedException, UnregisteredRecipientException;

    SendMessageResults sendEndSessionMessage(Set<RecipientIdentifier.Single> recipients) throws IOException;

-    void deleteRecipient(RecipientIdentifier.Single recipient) throws IOException;
+    void deleteRecipient(RecipientIdentifier.Single recipient);

-    void deleteContact(RecipientIdentifier.Single recipient) throws IOException;
+    void deleteContact(RecipientIdentifier.Single recipient);

    void setContactName(
            RecipientIdentifier.Single recipient, String name
-    ) throws NotMasterDeviceException, IOException;
+    ) throws NotMasterDeviceException, IOException, UnregisteredRecipientException;

    void setContactBlocked(
            RecipientIdentifier.Single recipient, boolean blocked
-    ) throws NotMasterDeviceException, IOException;
+    ) throws NotMasterDeviceException, IOException, UnregisteredRecipientException;

    void setGroupBlocked(
            GroupId groupId, boolean blocked
@@ -193,7 +193,7 @@ public interface Manager extends Closeable {

    void setExpirationTimer(
            RecipientIdentifier.Single recipient, int messageExpirationTimer
-    ) throws IOException;
+    ) throws IOException, UnregisteredRecipientException;

    URI uploadStickerPack(File path) throws IOException, StickerPackInvalidException;

@@ -245,13 +245,19 @@ public interface Manager extends Closeable {

    List<Identity> getIdentities(RecipientIdentifier.Single recipient);

-    boolean trustIdentityVerified(RecipientIdentifier.Single recipient, byte[] fingerprint);
+    boolean trustIdentityVerified(
+            RecipientIdentifier.Single recipient, byte[] fingerprint
+    ) throws UnregisteredRecipientException;

-    boolean trustIdentityVerifiedSafetyNumber(RecipientIdentifier.Single recipient, String safetyNumber);
+    boolean trustIdentityVerifiedSafetyNumber(
+            RecipientIdentifier.Single recipient, String safetyNumber
+    ) throws UnregisteredRecipientException;

-    boolean trustIdentityVerifiedSafetyNumber(RecipientIdentifier.Single recipient, byte[] safetyNumber);
+    boolean trustIdentityVerifiedSafetyNumber(
+            RecipientIdentifier.Single recipient, byte[] safetyNumber
+    ) throws UnregisteredRecipientException;

-    boolean trustIdentityAllKeys(RecipientIdentifier.Single recipient);
+    boolean trustIdentityAllKeys(RecipientIdentifier.Single recipient) throws UnregisteredRecipientException;

    void addClosedListener(Runnable listener);

--- a/lib/src/main/java/org/asamk/signal/manager/ManagerImpl.java
+++ b/lib/src/main/java/org/asamk/signal/manager/ManagerImpl.java
@@ -30,6 +30,7 @@ import org.asamk.signal.manager.api.SendGroupMessageResults;
 import org.asamk.signal.manager.api.SendMessageResult;
 import org.asamk.signal.manager.api.SendMessageResults;
 import org.asamk.signal.manager.api.TypingAction;
+import org.asamk.signal.manager.api.UnregisteredRecipientException;
 import org.asamk.signal.manager.api.UpdateGroup;
 import org.asamk.signal.manager.config.ServiceEnvironmentConfig;
 import org.asamk.signal.manager.groups.GroupId;
@@ -76,7 +77,6 @@ import org.whispersystems.signalservice.api.messages.SignalServiceEnvelope;
 import org.whispersystems.signalservice.api.messages.SignalServiceReceiptMessage;
 import org.whispersystems.signalservice.api.messages.SignalServiceTypingMessage;
 import org.whispersystems.signalservice.api.push.ACI;
-import org.whispersystems.signalservice.api.push.SignalServiceAddress;
 import org.whispersystems.signalservice.api.push.exceptions.AuthorizationFailedException;
 import org.whispersystems.signalservice.api.util.DeviceNameUtil;
 import org.whispersystems.signalservice.api.util.InvalidNumberException;
@@ -506,7 +506,7 @@ public class ManagerImpl implements Manager {
    }

    @Override
-    public Profile getRecipientProfile(RecipientIdentifier.Single recipient) throws IOException {
+    public Profile getRecipientProfile(RecipientIdentifier.Single recipient) throws IOException, UnregisteredRecipientException {
        return profileHelper.getRecipientProfile(recipientHelper.resolveRecipient(recipient));
    }

@@ -556,7 +556,7 @@ public class ManagerImpl implements Manager {
    @Override
    public SendGroupMessageResults quitGroup(
            GroupId groupId, Set<RecipientIdentifier.Single> groupAdmins
-    ) throws GroupNotFoundException, IOException, NotAGroupMemberException, LastGroupAdminException {
+    ) throws GroupNotFoundException, IOException, NotAGroupMemberException, LastGroupAdminException, UnregisteredRecipientException {
        final var newAdmins = recipientHelper.resolveRecipients(groupAdmins);
        return groupHelper.quitGroup(groupId, newAdmins);
    }
@@ -569,7 +569,7 @@ public class ManagerImpl implements Manager {
    @Override
    public Pair<GroupId, SendGroupMessageResults> createGroup(
            String name, Set<RecipientIdentifier.Single> members, File avatarFile
-    ) throws IOException, AttachmentInvalidException {
+    ) throws IOException, AttachmentInvalidException, UnregisteredRecipientException {
        return groupHelper.createGroup(name,
                members == null ? null : recipientHelper.resolveRecipients(members),
                avatarFile);
@@ -578,7 +578,7 @@ public class ManagerImpl implements Manager {
    @Override
    public SendGroupMessageResults updateGroup(
            final GroupId groupId, final UpdateGroup updateGroup
-    ) throws IOException, GroupNotFoundException, AttachmentInvalidException, NotAGroupMemberException, GroupSendingNotAllowedException {
+    ) throws IOException, GroupNotFoundException, AttachmentInvalidException, NotAGroupMemberException, GroupSendingNotAllowedException, UnregisteredRecipientException {
        return groupHelper.updateGroup(groupId,
                updateGroup.getName(),
                updateGroup.getDescription(),
@@ -614,12 +614,17 @@ public class ManagerImpl implements Manager {
        messageBuilder.withTimestamp(timestamp);
        for (final var recipient : recipients) {
            if (recipient instanceof RecipientIdentifier.Single single) {
-                final var recipientId = recipientHelper.resolveRecipient(single);
-                final var result = sendHelper.sendMessage(messageBuilder, recipientId);
-                results.put(recipient,
-                        List.of(SendMessageResult.from(result,
-                                account.getRecipientStore(),
-                                account.getRecipientStore()::resolveRecipientAddress)));
+                try {
+                    final var recipientId = recipientHelper.resolveRecipient(single);
+                    final var result = sendHelper.sendMessage(messageBuilder, recipientId);
+                    results.put(recipient,
+                            List.of(SendMessageResult.from(result,
+                                    account.getRecipientStore(),
+                                    account.getRecipientStore()::resolveRecipientAddress)));
+                } catch (UnregisteredRecipientException e) {
+                    results.put(recipient,
+                            List.of(SendMessageResult.unregisteredFailure(single.toPartialRecipientAddress())));
+                }
            } else if (recipient instanceof RecipientIdentifier.NoteToSelf) {
                final var result = sendHelper.sendSelfMessage(messageBuilder);
                results.put(recipient,
@@ -645,14 +650,19 @@ public class ManagerImpl implements Manager {
        var results = new HashMap<RecipientIdentifier, List<SendMessageResult>>();
        final var timestamp = System.currentTimeMillis();
        for (var recipient : recipients) {
-            if (recipient instanceof RecipientIdentifier.Single) {
+            if (recipient instanceof RecipientIdentifier.Single single) {
                final var message = new SignalServiceTypingMessage(action, timestamp, Optional.absent());
-                final var recipientId = recipientHelper.resolveRecipient((RecipientIdentifier.Single) recipient);
-                final var result = sendHelper.sendTypingMessage(message, recipientId);
-                results.put(recipient,
-                        List.of(SendMessageResult.from(result,
-                                account.getRecipientStore(),
-                                account.getRecipientStore()::resolveRecipientAddress)));
+                try {
+                    final var recipientId = recipientHelper.resolveRecipient(single);
+                    final var result = sendHelper.sendTypingMessage(message, recipientId);
+                    results.put(recipient,
+                            List.of(SendMessageResult.from(result,
+                                    account.getRecipientStore(),
+                                    account.getRecipientStore()::resolveRecipientAddress)));
+                } catch (UnregisteredRecipientException e) {
+                    results.put(recipient,
+                            List.of(SendMessageResult.unregisteredFailure(single.toPartialRecipientAddress())));
+                }
            } else if (recipient instanceof RecipientIdentifier.Group) {
                final var groupId = ((RecipientIdentifier.Group) recipient).groupId();
                final var message = new SignalServiceTypingMessage(action, timestamp, Optional.of(groupId.serialize()));
@@ -684,12 +694,7 @@ public class ManagerImpl implements Manager {
                messageIds,
                timestamp);

-        final var result = sendHelper.sendReceiptMessage(receiptMessage, recipientHelper.resolveRecipient(sender));
-        return new SendMessageResults(timestamp,
-                Map.of(sender,
-                        List.of(SendMessageResult.from(result,
-                                account.getRecipientStore(),
-                                account.getRecipientStore()::resolveRecipientAddress))));
+        return sendReceiptMessage(sender, timestamp, receiptMessage);
    }

    @Override
@@ -701,18 +706,31 @@ public class ManagerImpl implements Manager {
                messageIds,
                timestamp);

-        final var result = sendHelper.sendReceiptMessage(receiptMessage, recipientHelper.resolveRecipient(sender));
-        return new SendMessageResults(timestamp,
-                Map.of(sender,
-                        List.of(SendMessageResult.from(result,
-                                account.getRecipientStore(),
-                                account.getRecipientStore()::resolveRecipientAddress))));
+        return sendReceiptMessage(sender, timestamp, receiptMessage);
+    }
+
+    private SendMessageResults sendReceiptMessage(
+            final RecipientIdentifier.Single sender,
+            final long timestamp,
+            final SignalServiceReceiptMessage receiptMessage
+    ) throws IOException {
+        try {
+            final var result = sendHelper.sendReceiptMessage(receiptMessage, recipientHelper.resolveRecipient(sender));
+            return new SendMessageResults(timestamp,
+                    Map.of(sender,
+                            List.of(SendMessageResult.from(result,
+                                    account.getRecipientStore(),
+                                    account.getRecipientStore()::resolveRecipientAddress))));
+        } catch (UnregisteredRecipientException e) {
+            return new SendMessageResults(timestamp,
+                    Map.of(sender, List.of(SendMessageResult.unregisteredFailure(sender.toPartialRecipientAddress()))));
+        }
    }

    @Override
    public SendMessageResults sendMessage(
            Message message, Set<RecipientIdentifier> recipients
-    ) throws IOException, AttachmentInvalidException, NotAGroupMemberException, GroupNotFoundException, GroupSendingNotAllowedException {
+    ) throws IOException, AttachmentInvalidException, NotAGroupMemberException, GroupNotFoundException, GroupSendingNotAllowedException, UnregisteredRecipientException {
        final var messageBuilder = SignalServiceDataMessage.newBuilder();
        applyMessage(messageBuilder, message);
        return sendMessage(messageBuilder, recipients);
@@ -720,7 +738,7 @@ public class ManagerImpl implements Manager {

    private void applyMessage(
            final SignalServiceDataMessage.Builder messageBuilder, final Message message
-    ) throws AttachmentInvalidException, IOException {
+    ) throws AttachmentInvalidException, IOException, UnregisteredRecipientException {
        messageBuilder.withBody(message.messageText());
        final var attachments = message.attachments();
        if (attachments != null) {
@@ -739,7 +757,7 @@ public class ManagerImpl implements Manager {
        }
    }

-    private ArrayList<SignalServiceDataMessage.Mention> resolveMentions(final List<Message.Mention> mentionList) throws IOException {
+    private ArrayList<SignalServiceDataMessage.Mention> resolveMentions(final List<Message.Mention> mentionList) throws IOException, UnregisteredRecipientException {
        final var mentions = new ArrayList<SignalServiceDataMessage.Mention>();
        for (final var m : mentionList) {
            final var recipientId = recipientHelper.resolveRecipient(m.recipient());
@@ -765,7 +783,7 @@ public class ManagerImpl implements Manager {
            RecipientIdentifier.Single targetAuthor,
            long targetSentTimestamp,
            Set<RecipientIdentifier> recipients
-    ) throws IOException, NotAGroupMemberException, GroupNotFoundException, GroupSendingNotAllowedException {
+    ) throws IOException, NotAGroupMemberException, GroupNotFoundException, GroupSendingNotAllowedException, UnregisteredRecipientException {
        var targetAuthorRecipientId = recipientHelper.resolveRecipient(targetAuthor);
        var reaction = new SignalServiceDataMessage.Reaction(emoji,
                remove,
@@ -786,26 +804,32 @@ public class ManagerImpl implements Manager {
            throw new AssertionError(e);
        } finally {
            for (var recipient : recipients) {
-                final var recipientId = recipientHelper.resolveRecipient(recipient);
+                final RecipientId recipientId;
+                try {
+                    recipientId = recipientHelper.resolveRecipient(recipient);
+                } catch (UnregisteredRecipientException e) {
+                    continue;
+                }
                account.getSessionStore().deleteAllSessions(recipientId);
            }
        }
    }

    @Override
-    public void deleteRecipient(final RecipientIdentifier.Single recipient) throws IOException {
-        account.removeRecipient(recipientHelper.resolveRecipient(recipient));
+    public void deleteRecipient(final RecipientIdentifier.Single recipient) {
+        account.removeRecipient(account.getRecipientStore().resolveRecipient(recipient.toPartialRecipientAddress()));
    }

    @Override
-    public void deleteContact(final RecipientIdentifier.Single recipient) throws IOException {
-        account.getContactStore().deleteContact(recipientHelper.resolveRecipient(recipient));
+    public void deleteContact(final RecipientIdentifier.Single recipient) {
+        account.getContactStore()
+                .deleteContact(account.getRecipientStore().resolveRecipient(recipient.toPartialRecipientAddress()));
    }

    @Override
    public void setContactName(
            RecipientIdentifier.Single recipient, String name
-    ) throws NotMasterDeviceException, IOException {
+    ) throws NotMasterDeviceException, IOException, UnregisteredRecipientException {
        if (!account.isMasterDevice()) {
            throw new NotMasterDeviceException();
        }
@@ -815,12 +839,12 @@ public class ManagerImpl implements Manager {
    @Override
    public void setContactBlocked(
            RecipientIdentifier.Single recipient, boolean blocked
-    ) throws NotMasterDeviceException, IOException {
+    ) throws NotMasterDeviceException, IOException, UnregisteredRecipientException {
        if (!account.isMasterDevice()) {
            throw new NotMasterDeviceException();
        }
        contactHelper.setContactBlocked(recipientHelper.resolveRecipient(recipient), blocked);
-        // TODO cycle our profile key
+        // TODO cycle our profile key, if we're not together in a group with recipient
        syncHelper.sendBlockedList();
    }

@@ -842,7 +866,7 @@ public class ManagerImpl implements Manager {
    @Override
    public void setExpirationTimer(
            RecipientIdentifier.Single recipient, int messageExpirationTimer
-    ) throws IOException {
+    ) throws IOException, UnregisteredRecipientException {
        var recipientId = recipientHelper.resolveRecipient(recipient);
        contactHelper.setExpirationTimer(recipientId, messageExpirationTimer);
        final var messageBuilder = SignalServiceDataMessage.newBuilder().asExpirationUpdate();
@@ -1095,9 +1119,8 @@ public class ManagerImpl implements Manager {
            logger.debug("Checking for new message from server");
            try {
                var result = signalWebSocket.readOrEmpty(timeout.toMillis(), envelope1 -> {
-                    final var recipientId = envelope1.hasSourceUuid()
-                            ? resolveRecipient(envelope1.getSourceAddress())
-                            : null;
+                    final var recipientId = envelope1.hasSourceUuid() ? account.getRecipientStore()
+                            .resolveRecipient(envelope1.getSourceAddress()) : null;
                    // store message on disk, before acknowledging receipt to the server
                    cachedMessage[0] = account.getMessageCache().cacheMessage(envelope1, recipientId);
                });
@@ -1234,7 +1257,7 @@ public class ManagerImpl implements Manager {
        final RecipientId recipientId;
        try {
            recipientId = recipientHelper.resolveRecipient(recipient);
-        } catch (IOException e) {
+        } catch (IOException | UnregisteredRecipientException e) {
            return false;
        }
        return contactHelper.isContactBlocked(recipientId);
@@ -1259,7 +1282,7 @@ public class ManagerImpl implements Manager {
        final RecipientId recipientId;
        try {
            recipientId = recipientHelper.resolveRecipient(recipient);
-        } catch (IOException e) {
+        } catch (IOException | UnregisteredRecipientException e) {
            return null;
        }

@@ -1268,7 +1291,7 @@ public class ManagerImpl implements Manager {
            return contact.getName();
        }

-        final var profile = getRecipientProfile(recipientId);
+        final var profile = profileHelper.getRecipientProfile(recipientId);
        if (profile != null) {
            return profile.getDisplayName();
        }
@@ -1311,7 +1334,7 @@ public class ManagerImpl implements Manager {
        IdentityInfo identity;
        try {
            identity = account.getIdentityKeyStore().getIdentity(recipientHelper.resolveRecipient(recipient));
-        } catch (IOException e) {
+        } catch (IOException | UnregisteredRecipientException e) {
            identity = null;
        }
        return identity == null ? List.of() : List.of(toIdentity(identity));
@@ -1324,7 +1347,9 @@ public class ManagerImpl implements Manager {
     * @param fingerprint Fingerprint
     */
    @Override
-    public boolean trustIdentityVerified(RecipientIdentifier.Single recipient, byte[] fingerprint) {
+    public boolean trustIdentityVerified(
+            RecipientIdentifier.Single recipient, byte[] fingerprint
+    ) throws UnregisteredRecipientException {
        RecipientId recipientId;
        try {
            recipientId = recipientHelper.resolveRecipient(recipient);
@@ -1345,7 +1370,9 @@ public class ManagerImpl implements Manager {
     * @param safetyNumber Safety number
     */
    @Override
-    public boolean trustIdentityVerifiedSafetyNumber(RecipientIdentifier.Single recipient, String safetyNumber) {
+    public boolean trustIdentityVerifiedSafetyNumber(
+            RecipientIdentifier.Single recipient, String safetyNumber
+    ) throws UnregisteredRecipientException {
        RecipientId recipientId;
        try {
            recipientId = recipientHelper.resolveRecipient(recipient);
@@ -1366,7 +1393,9 @@ public class ManagerImpl implements Manager {
     * @param safetyNumber Scannable safety number
     */
    @Override
-    public boolean trustIdentityVerifiedSafetyNumber(RecipientIdentifier.Single recipient, byte[] safetyNumber) {
+    public boolean trustIdentityVerifiedSafetyNumber(
+            RecipientIdentifier.Single recipient, byte[] safetyNumber
+    ) throws UnregisteredRecipientException {
        RecipientId recipientId;
        try {
            recipientId = recipientHelper.resolveRecipient(recipient);
@@ -1386,7 +1415,7 @@ public class ManagerImpl implements Manager {
     * @param recipient account of the identity
     */
    @Override
-    public boolean trustIdentityAllKeys(RecipientIdentifier.Single recipient) {
+    public boolean trustIdentityAllKeys(RecipientIdentifier.Single recipient) throws UnregisteredRecipientException {
        RecipientId recipientId;
        try {
            recipientId = recipientHelper.resolveRecipient(recipient);
@@ -1414,10 +1443,6 @@ public class ManagerImpl implements Manager {
        this.identityHelper.handleIdentityFailure(recipientId, identityFailure);
    }

-    private RecipientId resolveRecipient(SignalServiceAddress address) {
-        return account.getRecipientStore().resolveRecipient(address);
-    }
-
    @Override
    public void close() throws IOException {
        Thread thread;
--- a/lib/src/main/java/org/asamk/signal/manager/api/RecipientIdentifier.java
+++ b/lib/src/main/java/org/asamk/signal/manager/api/RecipientIdentifier.java
@@ -50,6 +50,8 @@ public sealed interface RecipientIdentifier {
            }
            throw new AssertionError("RecipientAddress without identifier");
        }
+
+        RecipientAddress toPartialRecipientAddress();
    }

    record Uuid(UUID uuid) implements Single {
@@ -58,6 +60,11 @@ public sealed interface RecipientIdentifier {
        public String getIdentifier() {
            return uuid.toString();
        }
+
+        @Override
+        public RecipientAddress toPartialRecipientAddress() {
+            return new RecipientAddress(uuid);
+        }
    }

    record Number(String number) implements Single {
@@ -66,6 +73,11 @@ public sealed interface RecipientIdentifier {
        public String getIdentifier() {
            return number;
        }
+
+        @Override
+        public RecipientAddress toPartialRecipientAddress() {
+            return new RecipientAddress(null, number);
+        }
    }

    record Group(GroupId groupId) implements RecipientIdentifier {
--- a/lib/src/main/java/org/asamk/signal/manager/api/UnregisteredRecipientException.java
+++ b/lib/src/main/java/org/asamk/signal/manager/api/UnregisteredRecipientException.java
@@ -0,0 +1,17 @@
+package org.asamk.signal.manager.api;
+
+import org.asamk.signal.manager.storage.recipients.RecipientAddress;
+
+public class UnregisteredRecipientException extends Exception {
+
+    private final RecipientAddress sender;
+
+    public UnregisteredRecipientException(final RecipientAddress sender) {
+        super("Unregistered user: " + sender.getIdentifier());
+        this.sender = sender;
+    }
+
+    public RecipientAddress getSender() {
+        return sender;
+    }
+}
--- a/lib/src/main/java/org/asamk/signal/manager/helper/RecipientHelper.java
+++ b/lib/src/main/java/org/asamk/signal/manager/helper/RecipientHelper.java
@@ -2,16 +2,17 @@ package org.asamk.signal.manager.helper;

 import org.asamk.signal.manager.SignalDependencies;
 import org.asamk.signal.manager.api.RecipientIdentifier;
+import org.asamk.signal.manager.api.UnregisteredRecipientException;
 import org.asamk.signal.manager.config.ServiceConfig;
 import org.asamk.signal.manager.config.ServiceEnvironmentConfig;
 import org.asamk.signal.manager.storage.SignalAccount;
+import org.asamk.signal.manager.storage.recipients.RecipientAddress;
 import org.asamk.signal.manager.storage.recipients.RecipientId;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.whispersystems.libsignal.InvalidKeyException;
 import org.whispersystems.signalservice.api.push.ACI;
 import org.whispersystems.signalservice.api.push.SignalServiceAddress;
-import org.whispersystems.signalservice.api.push.exceptions.UnregisteredUserException;
 import org.whispersystems.signalservice.internal.contacts.crypto.Quote;
 import org.whispersystems.signalservice.internal.contacts.crypto.UnauthenticatedQuoteException;
 import org.whispersystems.signalservice.internal.contacts.crypto.UnauthenticatedResponseException;
@@ -53,7 +54,7 @@ public class RecipientHelper {
        final ACI aci;
        try {
            aci = getRegisteredUser(number);
-        } catch (IOException e) {
+        } catch (UnregisteredRecipientException | IOException e) {
            logger.warn("Failed to get uuid for e164 number: {}", number, e);
            // Return SignalServiceAddress with unknown UUID
            return address.toSignalServiceAddress();
@@ -63,7 +64,7 @@ public class RecipientHelper {
                .toSignalServiceAddress();
    }

-    public Set<RecipientId> resolveRecipients(Collection<RecipientIdentifier.Single> recipients) throws IOException {
+    public Set<RecipientId> resolveRecipients(Collection<RecipientIdentifier.Single> recipients) throws IOException, UnregisteredRecipientException {
        final var recipientIds = new HashSet<RecipientId>(recipients.size());
        for (var number : recipients) {
            final var recipientId = resolveRecipient(number);
@@ -72,7 +73,7 @@ public class RecipientHelper {
        return recipientIds;
    }

-    public RecipientId resolveRecipient(final RecipientIdentifier.Single recipient) throws IOException {
+    public RecipientId resolveRecipient(final RecipientIdentifier.Single recipient) throws IOException, UnregisteredRecipientException {
        if (recipient instanceof RecipientIdentifier.Uuid uuidRecipient) {
            return account.getRecipientStore().resolveRecipient(ACI.from(uuidRecipient.uuid()));
        } else {
@@ -80,14 +81,14 @@ public class RecipientHelper {
            return account.getRecipientStore().resolveRecipient(number, () -> {
                try {
                    return getRegisteredUser(number);
-                } catch (IOException e) {
+                } catch (Exception e) {
                    return null;
                }
            });
        }
    }

-    public RecipientId refreshRegisteredUser(RecipientId recipientId) throws IOException {
+    public RecipientId refreshRegisteredUser(RecipientId recipientId) throws IOException, UnregisteredRecipientException {
        final var address = resolveSignalServiceAddress(recipientId);
        if (!address.getNumber().isPresent()) {
            return recipientId;
@@ -115,16 +116,16 @@ public class RecipientHelper {
        return registeredUsers;
    }

-    private ACI getRegisteredUser(final String number) throws IOException {
+    private ACI getRegisteredUser(final String number) throws IOException, UnregisteredRecipientException {
        final Map<String, ACI> aciMap;
        try {
            aciMap = getRegisteredUsers(Set.of(number));
        } catch (NumberFormatException e) {
-            throw new UnregisteredUserException(number, e);
+            throw new UnregisteredRecipientException(new RecipientAddress(null, number));
        }
        final var uuid = aciMap.get(number);
        if (uuid == null) {
-            throw new UnregisteredUserException(number, null);
+            throw new UnregisteredRecipientException(new RecipientAddress(null, number));
        }
        return uuid;
    }
--- a/lib/src/main/java/org/asamk/signal/manager/helper/RecipientRegistrationRefresher.java
+++ b/lib/src/main/java/org/asamk/signal/manager/helper/RecipientRegistrationRefresher.java
@@ -1,10 +1,11 @@
 package org.asamk.signal.manager.helper;

+import org.asamk.signal.manager.api.UnregisteredRecipientException;
 import org.asamk.signal.manager.storage.recipients.RecipientId;

 import java.io.IOException;

 public interface RecipientRegistrationRefresher {

-    RecipientId refreshRecipientRegistration(RecipientId recipientId) throws IOException;
+    RecipientId refreshRecipientRegistration(RecipientId recipientId) throws IOException, UnregisteredRecipientException;
 }
--- a/lib/src/main/java/org/asamk/signal/manager/helper/SendHelper.java
+++ b/lib/src/main/java/org/asamk/signal/manager/helper/SendHelper.java
@@ -1,6 +1,7 @@
 package org.asamk.signal.manager.helper;

 import org.asamk.signal.manager.SignalDependencies;
+import org.asamk.signal.manager.api.UnregisteredRecipientException;
 import org.asamk.signal.manager.groups.GroupId;
 import org.asamk.signal.manager.groups.GroupNotFoundException;
 import org.asamk.signal.manager.groups.GroupSendingNotAllowedException;
@@ -494,7 +495,12 @@ public class SendHelper {
            try {
                return s.send(messageSender, address, unidentifiedAccessHelper.getAccessFor(recipientId));
            } catch (UnregisteredUserException e) {
-                final var newRecipientId = recipientRegistrationRefresher.refreshRecipientRegistration(recipientId);
+                final RecipientId newRecipientId;
+                try {
+                    newRecipientId = recipientRegistrationRefresher.refreshRecipientRegistration(recipientId);
+                } catch (UnregisteredRecipientException ex) {
+                    return SendMessageResult.unregisteredFailure(address);
+                }
                address = addressResolver.resolveSignalServiceAddress(newRecipientId);
                return s.send(messageSender, address, unidentifiedAccessHelper.getAccessFor(newRecipientId));
            }
--- a/lib/src/main/java/org/asamk/signal/manager/storage/recipients/RecipientStore.java
+++ b/lib/src/main/java/org/asamk/signal/manager/storage/recipients/RecipientStore.java
@@ -3,6 +3,7 @@ package org.asamk.signal.manager.storage.recipients;
 import com.fasterxml.jackson.databind.ObjectMapper;

 import org.asamk.signal.manager.api.Pair;
+import org.asamk.signal.manager.api.UnregisteredRecipientException;
 import org.asamk.signal.manager.storage.Utils;
 import org.asamk.signal.manager.storage.contacts.ContactsStore;
 import org.asamk.signal.manager.storage.profiles.ProfileStore;
@@ -13,7 +14,6 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.whispersystems.signalservice.api.push.ACI;
 import org.whispersystems.signalservice.api.push.SignalServiceAddress;
-import org.whispersystems.signalservice.api.push.exceptions.UnregisteredUserException;
 import org.whispersystems.signalservice.api.util.UuidUtil;

 import java.io.ByteArrayInputStream;
@@ -144,7 +144,7 @@ public class RecipientStore implements RecipientResolver, ContactsStore, Profile

    @Override
    public RecipientId resolveRecipient(ACI aci) {
-        return resolveRecipient(new RecipientAddress(aci == null ? null : aci.uuid()), false);
+        return resolveRecipient(new RecipientAddress(aci.uuid()), false);
    }

    @Override
@@ -160,7 +160,7 @@ public class RecipientStore implements RecipientResolver, ContactsStore, Profile

    public RecipientId resolveRecipient(
            final String number, Supplier<ACI> aciSupplier
-    ) throws UnregisteredUserException {
+    ) throws UnregisteredRecipientException {
        final Optional<Recipient> byNumber;
        synchronized (recipients) {
            byNumber = findByNumberLocked(number);
@@ -168,7 +168,7 @@ public class RecipientStore implements RecipientResolver, ContactsStore, Profile
        if (byNumber.isEmpty() || byNumber.get().getAddress().uuid().isEmpty()) {
            final var aci = aciSupplier.get();
            if (aci == null) {
-                throw new UnregisteredUserException(number, null);
+                throw new UnregisteredRecipientException(new RecipientAddress(null, number));
            }

            return resolveRecipient(new RecipientAddress(aci.uuid(), number), false);
--- a/src/main/java/org/asamk/Signal.java
+++ b/src/main/java/org/asamk/Signal.java
@@ -615,5 +615,12 @@ public interface Signal extends DBusInterface {
                super("Untrusted identity: " + message);
            }
        }
+
+        class UnregisteredRecipient extends DBusExecutionException {
+
+            public UnregisteredRecipient(final String message) {
+                super("Unregistered recipient: " + message);
+            }
+        }
    }
 }
--- a/src/main/java/org/asamk/signal/commands/BlockCommand.java
+++ b/src/main/java/org/asamk/signal/commands/BlockCommand.java
@@ -8,6 +8,7 @@ import org.asamk.signal.commands.exceptions.UnexpectedErrorException;
 import org.asamk.signal.commands.exceptions.UserErrorException;
 import org.asamk.signal.manager.Manager;
 import org.asamk.signal.manager.NotMasterDeviceException;
+import org.asamk.signal.manager.api.UnregisteredRecipientException;
 import org.asamk.signal.manager.groups.GroupNotFoundException;
 import org.asamk.signal.output.OutputWriter;
 import org.asamk.signal.util.CommandUtil;
@@ -44,6 +45,8 @@ public class BlockCommand implements JsonRpcLocalCommand {
                throw new UserErrorException("This command doesn't work on linked devices.");
            } catch (IOException e) {
                throw new UnexpectedErrorException("Failed to sync block to linked devices: " + e.getMessage(), e);
+            } catch (UnregisteredRecipientException e) {
+                throw new UserErrorException("The user " + e.getSender().getIdentifier() + " is not registered.");
            }
        }

--- a/src/main/java/org/asamk/signal/commands/QuitGroupCommand.java
+++ b/src/main/java/org/asamk/signal/commands/QuitGroupCommand.java
@@ -8,6 +8,7 @@ import org.asamk.signal.commands.exceptions.CommandException;
 import org.asamk.signal.commands.exceptions.IOErrorException;
 import org.asamk.signal.commands.exceptions.UserErrorException;
 import org.asamk.signal.manager.Manager;
+import org.asamk.signal.manager.api.UnregisteredRecipientException;
 import org.asamk.signal.manager.groups.GroupNotFoundException;
 import org.asamk.signal.manager.groups.LastGroupAdminException;
 import org.asamk.signal.manager.groups.NotAGroupMemberException;
@@ -70,6 +71,8 @@ public class QuitGroupCommand implements JsonRpcLocalCommand {
            throw new UserErrorException("Failed to send to group: " + e.getMessage());
        } catch (LastGroupAdminException e) {
            throw new UserErrorException("You need to specify a new admin with --admin: " + e.getMessage());
+        } catch (UnregisteredRecipientException e) {
+            throw new UserErrorException("The user " + e.getSender().getIdentifier() + " is not registered.");
        }
    }
 }
--- a/src/main/java/org/asamk/signal/commands/RemoveContactCommand.java
+++ b/src/main/java/org/asamk/signal/commands/RemoveContactCommand.java
@@ -5,13 +5,10 @@ import net.sourceforge.argparse4j.inf.Namespace;
 import net.sourceforge.argparse4j.inf.Subparser;

 import org.asamk.signal.commands.exceptions.CommandException;
-import org.asamk.signal.commands.exceptions.IOErrorException;
 import org.asamk.signal.manager.Manager;
 import org.asamk.signal.output.OutputWriter;
 import org.asamk.signal.util.CommandUtil;

-import java.io.IOException;
-
 public class RemoveContactCommand implements JsonRpcLocalCommand {

    @Override
@@ -36,14 +33,10 @@ public class RemoveContactCommand implements JsonRpcLocalCommand {
        var recipient = CommandUtil.getSingleRecipientIdentifier(recipientString, m.getSelfNumber());

        var forget = Boolean.TRUE == ns.getBoolean("forget");
-        try {
-            if (forget) {
-                m.deleteRecipient(recipient);
-            } else {
-                m.deleteContact(recipient);
-            }
-        } catch (IOException e) {
-            throw new IOErrorException("Remove contact error: " + e.getMessage(), e);
+        if (forget) {
+            m.deleteRecipient(recipient);
+        } else {
+            m.deleteContact(recipient);
        }
    }
 }
--- a/src/main/java/org/asamk/signal/commands/SendCommand.java
+++ b/src/main/java/org/asamk/signal/commands/SendCommand.java
@@ -11,6 +11,7 @@ import org.asamk.signal.manager.AttachmentInvalidException;
 import org.asamk.signal.manager.Manager;
 import org.asamk.signal.manager.api.Message;
 import org.asamk.signal.manager.api.RecipientIdentifier;
+import org.asamk.signal.manager.api.UnregisteredRecipientException;
 import org.asamk.signal.manager.groups.GroupNotFoundException;
 import org.asamk.signal.manager.groups.GroupSendingNotAllowedException;
 import org.asamk.signal.manager.groups.NotAGroupMemberException;
@@ -143,6 +144,8 @@ public class SendCommand implements JsonRpcLocalCommand {
                    .getSimpleName() + ")", e);
        } catch (GroupNotFoundException | NotAGroupMemberException | GroupSendingNotAllowedException e) {
            throw new UserErrorException(e.getMessage());
+        } catch (UnregisteredRecipientException e) {
+            throw new UserErrorException("The user " + e.getSender().getIdentifier() + " is not registered.");
        }
    }

--- a/src/main/java/org/asamk/signal/commands/SendReactionCommand.java
+++ b/src/main/java/org/asamk/signal/commands/SendReactionCommand.java
@@ -8,6 +8,7 @@ import org.asamk.signal.commands.exceptions.CommandException;
 import org.asamk.signal.commands.exceptions.UnexpectedErrorException;
 import org.asamk.signal.commands.exceptions.UserErrorException;
 import org.asamk.signal.manager.Manager;
+import org.asamk.signal.manager.api.UnregisteredRecipientException;
 import org.asamk.signal.manager.groups.GroupNotFoundException;
 import org.asamk.signal.manager.groups.GroupSendingNotAllowedException;
 import org.asamk.signal.manager.groups.NotAGroupMemberException;
@@ -76,6 +77,8 @@ public class SendReactionCommand implements JsonRpcLocalCommand {
        } catch (IOException e) {
            throw new UnexpectedErrorException("Failed to send message: " + e.getMessage() + " (" + e.getClass()
                    .getSimpleName() + ")", e);
+        } catch (UnregisteredRecipientException e) {
+            throw new UserErrorException("The user " + e.getSender().getIdentifier() + " is not registered.");
        }
    }
 }
--- a/src/main/java/org/asamk/signal/commands/TrustCommand.java
+++ b/src/main/java/org/asamk/signal/commands/TrustCommand.java
@@ -7,6 +7,7 @@ import net.sourceforge.argparse4j.inf.Subparser;
 import org.asamk.signal.commands.exceptions.CommandException;
 import org.asamk.signal.commands.exceptions.UserErrorException;
 import org.asamk.signal.manager.Manager;
+import org.asamk.signal.manager.api.UnregisteredRecipientException;
 import org.asamk.signal.output.OutputWriter;
 import org.asamk.signal.util.CommandUtil;
 import org.asamk.signal.util.Hex;
@@ -40,7 +41,12 @@ public class TrustCommand implements JsonRpcLocalCommand {
        var recipentString = ns.getString("recipient");
        var recipient = CommandUtil.getSingleRecipientIdentifier(recipentString, m.getSelfNumber());
        if (Boolean.TRUE.equals(ns.getBoolean("trust-all-known-keys"))) {
-            boolean res = m.trustIdentityAllKeys(recipient);
+            boolean res;
+            try {
+                res = m.trustIdentityAllKeys(recipient);
+            } catch (UnregisteredRecipientException e) {
+                throw new UserErrorException("The user " + e.getSender().getIdentifier() + " is not registered.");
+            }
            if (!res) {
                throw new UserErrorException("Failed to set the trust for this number, make sure the number is correct.");
            }
@@ -60,13 +66,23 @@ public class TrustCommand implements JsonRpcLocalCommand {
                    throw new UserErrorException(
                            "Failed to parse the fingerprint, make sure the fingerprint is a correctly encoded hex string without additional characters.");
                }
-                boolean res = m.trustIdentityVerified(recipient, fingerprintBytes);
+                boolean res;
+                try {
+                    res = m.trustIdentityVerified(recipient, fingerprintBytes);
+                } catch (UnregisteredRecipientException e) {
+                    throw new UserErrorException("The user " + e.getSender().getIdentifier() + " is not registered.");
+                }
                if (!res) {
                    throw new UserErrorException(
                            "Failed to set the trust for the fingerprint of this number, make sure the number and the fingerprint are correct.");
                }
            } else if (safetyNumber.length() == 60) {
-                boolean res = m.trustIdentityVerifiedSafetyNumber(recipient, safetyNumber);
+                boolean res;
+                try {
+                    res = m.trustIdentityVerifiedSafetyNumber(recipient, safetyNumber);
+                } catch (UnregisteredRecipientException e) {
+                    throw new UserErrorException("The user " + e.getSender().getIdentifier() + " is not registered.");
+                }
                if (!res) {
                    throw new UserErrorException(
                            "Failed to set the trust for the safety number of this phone number, make sure the phone number and the safety number are correct.");
@@ -79,7 +95,12 @@ public class TrustCommand implements JsonRpcLocalCommand {
                    throw new UserErrorException(
                            "Safety number has invalid format, either specify the old hex fingerprint or the new safety number");
                }
-                boolean res = m.trustIdentityVerifiedSafetyNumber(recipient, scannableSafetyNumber);
+                boolean res;
+                try {
+                    res = m.trustIdentityVerifiedSafetyNumber(recipient, scannableSafetyNumber);
+                } catch (UnregisteredRecipientException e) {
+                    throw new UserErrorException("The user " + e.getSender().getIdentifier() + " is not registered.");
+                }
                if (!res) {
                    throw new UserErrorException(
                            "Failed to set the trust for the safety number of this phone number, make sure the phone number and the safety number are correct.");
--- a/src/main/java/org/asamk/signal/commands/UnblockCommand.java
+++ b/src/main/java/org/asamk/signal/commands/UnblockCommand.java
@@ -8,6 +8,7 @@ import org.asamk.signal.commands.exceptions.UnexpectedErrorException;
 import org.asamk.signal.commands.exceptions.UserErrorException;
 import org.asamk.signal.manager.Manager;
 import org.asamk.signal.manager.NotMasterDeviceException;
+import org.asamk.signal.manager.api.UnregisteredRecipientException;
 import org.asamk.signal.manager.groups.GroupNotFoundException;
 import org.asamk.signal.output.OutputWriter;
 import org.asamk.signal.util.CommandUtil;
@@ -44,6 +45,8 @@ public class UnblockCommand implements JsonRpcLocalCommand {
                throw new UserErrorException("This command doesn't work on linked devices.");
            } catch (IOException e) {
                throw new UnexpectedErrorException("Failed to sync unblock to linked devices: " + e.getMessage(), e);
+            } catch (UnregisteredRecipientException e) {
+                throw new UserErrorException("The user " + e.getSender().getIdentifier() + " is not registered.");
            }
        }

--- a/src/main/java/org/asamk/signal/commands/UpdateContactCommand.java
+++ b/src/main/java/org/asamk/signal/commands/UpdateContactCommand.java
@@ -8,6 +8,7 @@ import org.asamk.signal.commands.exceptions.IOErrorException;
 import org.asamk.signal.commands.exceptions.UserErrorException;
 import org.asamk.signal.manager.Manager;
 import org.asamk.signal.manager.NotMasterDeviceException;
+import org.asamk.signal.manager.api.UnregisteredRecipientException;
 import org.asamk.signal.output.OutputWriter;
 import org.asamk.signal.util.CommandUtil;

@@ -49,6 +50,8 @@ public class UpdateContactCommand implements JsonRpcLocalCommand {
            throw new IOErrorException("Update contact error: " + e.getMessage(), e);
        } catch (NotMasterDeviceException e) {
            throw new UserErrorException("This command doesn't work on linked devices.");
+        } catch (UnregisteredRecipientException e) {
+            throw new UserErrorException("The user " + e.getSender().getIdentifier() + " is not registered.");
        }
    }
 }
--- a/src/main/java/org/asamk/signal/commands/UpdateGroupCommand.java
+++ b/src/main/java/org/asamk/signal/commands/UpdateGroupCommand.java
@@ -10,6 +10,7 @@ import org.asamk.signal.commands.exceptions.UserErrorException;
 import org.asamk.signal.manager.AttachmentInvalidException;
 import org.asamk.signal.manager.Manager;
 import org.asamk.signal.manager.api.SendGroupMessageResults;
+import org.asamk.signal.manager.api.UnregisteredRecipientException;
 import org.asamk.signal.manager.api.UpdateGroup;
 import org.asamk.signal.manager.groups.GroupId;
 import org.asamk.signal.manager.groups.GroupLinkState;
@@ -167,6 +168,8 @@ public class UpdateGroupCommand implements JsonRpcLocalCommand {
            throw new UserErrorException("Failed to add avatar attachment for group\": " + e.getMessage());
        } catch (GroupNotFoundException | NotAGroupMemberException | GroupSendingNotAllowedException e) {
            throw new UserErrorException(e.getMessage());
+        } catch (UnregisteredRecipientException e) {
+            throw new UserErrorException("The user " + e.getSender().getIdentifier() + " is not registered.");
        } catch (IOException e) {
            throw new UnexpectedErrorException("Failed to send message: " + e.getMessage() + " (" + e.getClass()
                    .getSimpleName() + ")", e);
--- a/src/main/java/org/asamk/signal/dbus/DbusManagerImpl.java
+++ b/src/main/java/org/asamk/signal/dbus/DbusManagerImpl.java
@@ -392,12 +392,12 @@ public class DbusManagerImpl implements Manager {
    }

    @Override
-    public void deleteRecipient(final RecipientIdentifier.Single recipient) throws IOException {
+    public void deleteRecipient(final RecipientIdentifier.Single recipient) {
        signal.deleteRecipient(recipient.getIdentifier());
    }

    @Override
-    public void deleteContact(final RecipientIdentifier.Single recipient) throws IOException {
+    public void deleteContact(final RecipientIdentifier.Single recipient) {
        signal.deleteContact(recipient.getIdentifier());
    }

--- a/src/main/java/org/asamk/signal/dbus/DbusSignalImpl.java
+++ b/src/main/java/org/asamk/signal/dbus/DbusSignalImpl.java
@@ -16,6 +16,7 @@ import org.asamk.signal.manager.api.RecipientIdentifier;
 import org.asamk.signal.manager.api.SendMessageResult;
 import org.asamk.signal.manager.api.SendMessageResults;
 import org.asamk.signal.manager.api.TypingAction;
+import org.asamk.signal.manager.api.UnregisteredRecipientException;
 import org.asamk.signal.manager.api.UpdateGroup;
 import org.asamk.signal.manager.groups.GroupId;
 import org.asamk.signal.manager.groups.GroupInviteLinkUrl;
@@ -211,6 +212,8 @@ public class DbusSignalImpl implements Signal {
            throw new Error.Failure(e);
        } catch (GroupNotFoundException | NotAGroupMemberException | GroupSendingNotAllowedException e) {
            throw new Error.GroupNotFound(e.getMessage());
+        } catch (UnregisteredRecipientException e) {
+            throw new Error.UntrustedIdentity(e.getSender().getIdentifier() + " is not registered.");
        }
    }

@@ -272,6 +275,8 @@ public class DbusSignalImpl implements Signal {
            throw new Error.Failure(e.getMessage());
        } catch (GroupNotFoundException | NotAGroupMemberException | GroupSendingNotAllowedException e) {
            throw new Error.GroupNotFound(e.getMessage());
+        } catch (UnregisteredRecipientException e) {
+            throw new Error.UntrustedIdentity(e.getSender().getIdentifier() + " is not registered.");
        }
    }

@@ -351,6 +356,8 @@ public class DbusSignalImpl implements Signal {
            throw new Error.Failure(e.getMessage());
        } catch (GroupNotFoundException | NotAGroupMemberException | GroupSendingNotAllowedException e) {
            throw new Error.GroupNotFound(e.getMessage());
+        } catch (UnregisteredRecipientException e) {
+            throw new Error.UntrustedIdentity(e.getSender().getIdentifier() + " is not registered.");
        }
    }

@@ -366,20 +373,12 @@ public class DbusSignalImpl implements Signal {

    @Override
    public void deleteRecipient(final String recipient) throws Error.Failure {
-        try {
-            m.deleteRecipient(getSingleRecipientIdentifier(recipient, m.getSelfNumber()));
-        } catch (IOException e) {
-            throw new Error.Failure("Recipient not found");
-        }
+        m.deleteRecipient(getSingleRecipientIdentifier(recipient, m.getSelfNumber()));
    }

    @Override
    public void deleteContact(final String recipient) throws Error.Failure {
-        try {
-            m.deleteContact(getSingleRecipientIdentifier(recipient, m.getSelfNumber()));
-        } catch (IOException e) {
-            throw new Error.Failure("Contact not found");
-        }
+        m.deleteContact(getSingleRecipientIdentifier(recipient, m.getSelfNumber()));
    }

    @Override
@@ -395,6 +394,8 @@ public class DbusSignalImpl implements Signal {
            throw new Error.GroupNotFound(e.getMessage());
        } catch (AttachmentInvalidException e) {
            throw new Error.AttachmentInvalid(e.getMessage());
+        } catch (UnregisteredRecipientException e) {
+            throw new Error.UntrustedIdentity(e.getSender().getIdentifier() + " is not registered.");
        }
    }

@@ -449,6 +450,8 @@ public class DbusSignalImpl implements Signal {
            throw new Error.Failure(e.getMessage());
        } catch (GroupNotFoundException | NotAGroupMemberException | GroupSendingNotAllowedException e) {
            throw new Error.GroupNotFound(e.getMessage());
+        } catch (UnregisteredRecipientException e) {
+            throw new Error.UntrustedIdentity(e.getSender().getIdentifier() + " is not registered.");
        }
    }

@@ -468,6 +471,8 @@ public class DbusSignalImpl implements Signal {
            throw new Error.Failure("This command doesn't work on linked devices.");
        } catch (IOException e) {
            throw new Error.Failure("Contact is not registered.");
+        } catch (UnregisteredRecipientException e) {
+            throw new Error.UntrustedIdentity(e.getSender().getIdentifier() + " is not registered.");
        }
    }

@@ -477,6 +482,8 @@ public class DbusSignalImpl implements Signal {
            m.setExpirationTimer(getSingleRecipientIdentifier(number, m.getSelfNumber()), expiration);
        } catch (IOException e) {
            throw new Error.Failure(e.getMessage());
+        } catch (UnregisteredRecipientException e) {
+            throw new Error.UntrustedIdentity(e.getSender().getIdentifier() + " is not registered.");
        }
    }

@@ -488,6 +495,8 @@ public class DbusSignalImpl implements Signal {
            throw new Error.Failure("This command doesn't work on linked devices.");
        } catch (IOException e) {
            throw new Error.Failure(e.getMessage());
+        } catch (UnregisteredRecipientException e) {
+            throw new Error.UntrustedIdentity(e.getSender().getIdentifier() + " is not registered.");
        }
    }

@@ -584,6 +593,8 @@ public class DbusSignalImpl implements Signal {
            throw new Error.GroupNotFound(e.getMessage());
        } catch (AttachmentInvalidException e) {
            throw new Error.AttachmentInvalid(e.getMessage());
+        } catch (UnregisteredRecipientException e) {
+            throw new Error.UntrustedIdentity(e.getSender().getIdentifier() + " is not registered.");
        }
    }

@@ -707,7 +718,7 @@ public class DbusSignalImpl implements Signal {
                Profile profile = null;
                try {
                    profile = m.getRecipientProfile(RecipientIdentifier.Single.fromAddress(address));
-                } catch (IOException ignored) {
+                } catch (IOException | UnregisteredRecipientException ignored) {
                }
                if (profile != null && profile.getDisplayName().equals(name)) {
                    numbers.add(number);
@@ -726,6 +737,8 @@ public class DbusSignalImpl implements Signal {
            throw new Error.GroupNotFound(e.getMessage());
        } catch (IOException | LastGroupAdminException e) {
            throw new Error.Failure(e.getMessage());
+        } catch (UnregisteredRecipientException e) {
+            throw new Error.UntrustedIdentity(e.getSender().getIdentifier() + " is not registered.");
        }
    }

@@ -1149,6 +1162,8 @@ public class DbusSignalImpl implements Signal {
                throw new Error.Failure(e.getMessage());
            } catch (LastGroupAdminException e) {
                throw new Error.LastGroupAdmin(e.getMessage());
+            } catch (UnregisteredRecipientException e) {
+                throw new Error.UntrustedIdentity(e.getSender().getIdentifier() + " is not registered.");
            }
        }

@@ -1262,6 +1277,8 @@ public class DbusSignalImpl implements Signal {
                throw new Error.GroupNotFound(e.getMessage());
            } catch (AttachmentInvalidException e) {
                throw new Error.AttachmentInvalid(e.getMessage());
+            } catch (UnregisteredRecipientException e) {
+                throw new Error.UntrustedIdentity(e.getSender().getIdentifier() + " is not registered.");
            }
        }
    }