diff --git a/BTCPayServer/BTCPayNetworkProvider.Dogecoin.cs b/BTCPayServer/BTCPayNetworkProvider.Dogecoin.cs
index 9fbff33a9..e12ceaff7 100644
--- a/BTCPayServer/BTCPayNetworkProvider.Dogecoin.cs
+++ b/BTCPayServer/BTCPayNetworkProvider.Dogecoin.cs
@@ -20,7 +20,11 @@ namespace BTCPayServer
                 NBitcoinNetwork = nbxplorerNetwork.NBitcoinNetwork,
                 NBXplorerNetwork = nbxplorerNetwork,
                 UriScheme = "dogecoin",
-                DefaultRateRules = new[] { "DOGE_X = bittrex(DOGE_BTC) * BTC_X" },
+                DefaultRateRules = new[] 
+                {
+                                "DOGE_X = DOGE_BTC * BTC_X",
+                                "DOGE_BTC = bittrex(DOGE_BTC)"
+                },
                 CryptoImagePath = "imlegacy/dogecoin.png",
                 DefaultSettings = BTCPayDefaultSettings.GetDefaultSettings(NetworkType),
                 CoinType = NetworkType == NetworkType.Mainnet ? new KeyPath("3'") : new KeyPath("1'")
diff --git a/BTCPayServer/BTCPayServer.csproj b/BTCPayServer/BTCPayServer.csproj
index 2b36f82d5..ce03eb9b7 100644
--- a/BTCPayServer/BTCPayServer.csproj
+++ b/BTCPayServer/BTCPayServer.csproj
@@ -2,7 +2,7 @@
   <PropertyGroup>
     <OutputType>Exe</OutputType>
     <TargetFramework>netcoreapp2.0</TargetFramework>
-		<Version>1.0.2.3</Version>
+		<Version>1.0.2.4</Version>
     <NoWarn>NU1701,CA1816,CA1308,CA1810,CA2208</NoWarn>
   </PropertyGroup>
   <ItemGroup>
diff --git a/BTCPayServer/Controllers/ServerController.cs b/BTCPayServer/Controllers/ServerController.cs
index 54ec88151..2c10440d0 100644
--- a/BTCPayServer/Controllers/ServerController.cs
+++ b/BTCPayServer/Controllers/ServerController.cs
@@ -243,10 +243,7 @@ namespace BTCPayServer.Controllers
             {
                 try
                 {
-                    if(string.IsNullOrWhiteSpace(model.Settings.From)
-                       || string.IsNullOrWhiteSpace(model.TestEmail)
-                       || string.IsNullOrWhiteSpace(model.Settings.Login)
-                       || string.IsNullOrWhiteSpace(model.Settings.Server))
+                    if(!model.Settings.IsComplete())
                     {
                         model.StatusMessage = "Error: Required fields missing";
                         return View(model);
diff --git a/BTCPayServer/Rating/RateRules.cs b/BTCPayServer/Rating/RateRules.cs
index b7c7f20bc..617a24447 100644
--- a/BTCPayServer/Rating/RateRules.cs
+++ b/BTCPayServer/Rating/RateRules.cs
@@ -149,9 +149,10 @@ namespace BTCPayServer.Rating
                 (Pair: p, Priority: 0, Inverse: false),
                 (Pair: new CurrencyPair(p.Left, "X"), Priority: 1, Inverse: false),
                 (Pair: new CurrencyPair("X", p.Right), Priority: 1, Inverse: false),
-                (Pair: new CurrencyPair(invP.Left, "X"), Priority: 2, Inverse: true),
-                (Pair: new CurrencyPair("X", invP.Right), Priority: 2, Inverse: true),
-                (Pair: new CurrencyPair("X", "X"), Priority: 3, Inverse: false)
+                (Pair: invP, Priority: 2, Inverse: true),
+                (Pair: new CurrencyPair(invP.Left, "X"), Priority: 3, Inverse: true),
+                (Pair: new CurrencyPair("X", invP.Right), Priority: 3, Inverse: true),
+                (Pair: new CurrencyPair("X", "X"), Priority: 4, Inverse: false)
             })
             {
                 if (ruleList.ExpressionsByPair.TryGetValue(pair.Pair, out var expression))
diff --git a/BTCPayServer/Services/Mails/EmailSender.cs b/BTCPayServer/Services/Mails/EmailSender.cs
index c97c2cbbd..2e51db317 100644
--- a/BTCPayServer/Services/Mails/EmailSender.cs
+++ b/BTCPayServer/Services/Mails/EmailSender.cs
@@ -24,8 +24,8 @@ namespace BTCPayServer.Services.Mails
         }
         public async Task SendEmailAsync(string email, string subject, string message)
         {
-            var settings = await _Repository.GetSettingAsync<EmailSettings>();
-            if (settings == null)
+            var settings = await _Repository.GetSettingAsync<EmailSettings>() ?? new EmailSettings();
+            if (!settings.IsComplete())
             {
                 Logs.Configuration.LogWarning("Should have sent email, but email settings are not configured");
                 return;
@@ -36,8 +36,8 @@ namespace BTCPayServer.Services.Mails
 
         public async Task SendMailCore(string email, string subject, string message)
         {
-            var settings = await _Repository.GetSettingAsync<EmailSettings>();
-            if (settings == null)
+            var settings = await _Repository.GetSettingAsync<EmailSettings>() ?? new EmailSettings();
+            if (!settings.IsComplete())
                 throw new InvalidOperationException("Email settings not configured");
             var smtp = settings.CreateSmtpClient();
             MailMessage mail = new MailMessage(settings.From, email, subject, message);
diff --git a/BTCPayServer/Services/Mails/EmailSettings.cs b/BTCPayServer/Services/Mails/EmailSettings.cs
index 22840cc36..93b062eec 100644
--- a/BTCPayServer/Services/Mails/EmailSettings.cs
+++ b/BTCPayServer/Services/Mails/EmailSettings.cs
@@ -40,6 +40,18 @@ namespace BTCPayServer.Services.Mails
             get; set;
         }
 
+        public bool IsComplete()
+        {
+            SmtpClient smtp = null;
+            try
+            {
+                smtp = CreateSmtpClient();
+                return true;
+            }
+            catch { }
+            return false;
+        }
+
         public SmtpClient CreateSmtpClient()
         {
             SmtpClient client = new SmtpClient(Server, Port.Value);
diff --git a/BTCPayServer/Views/Stores/Rates.cshtml b/BTCPayServer/Views/Stores/Rates.cshtml
index 4aca36b81..9a2f7efbc 100644
--- a/BTCPayServer/Views/Stores/Rates.cshtml
+++ b/BTCPayServer/Views/Stores/Rates.cshtml
@@ -93,7 +93,19 @@
                             X_X = gdax(X_X);
                         </code>
                     </pre>
-                    <p>With <code>DOGE_USD</code> will be expanded to <code>bittrex(DOGE_BTC) * gdax(BTC_USD)</code>. And <code>DOGE_CAD</code> will be expanded to <code>bittrex(DOGE_BTC) * quadrigacx(BTC_CAD)</code></p>
+                    <p>With <code>DOGE_USD</code> will be expanded to <code>bittrex(DOGE_BTC) * gdax(BTC_USD)</code>. And <code>DOGE_CAD</code> will be expanded to <code>bittrex(DOGE_BTC) * quadrigacx(BTC_CAD)</code>. <br />
+                    However, we advise you to write it that way to increase coverage so that <code>DOGE_BTC</code> is also supported:</p>
+                    <pre>
+                        <code>
+                            DOGE_X = DOGE_BTC * BTC_X
+                            DOGE_BTC = bittrex(DOGE_BTC)
+                            X_CAD = quadrigacx(X_CAD);
+                            X_X = gdax(X_X);
+                        </code>
+                    </pre>
+                    <p>It is worth noting that the inverses of those pairs are automatically supported as well.<br />
+                    It means that the rule <code>USD_DOGE = 1 / DOGE_USD</code> implicitely exists.</p>
+
                 </div>
                 <div class="form-group">
                     <label asp-for="Script"></label>