diff --git a/Riot/Assets/en.lproj/Vector.strings b/Riot/Assets/en.lproj/Vector.strings
index d1677e9dd..30cc0e7b4 100644
--- a/Riot/Assets/en.lproj/Vector.strings
+++ b/Riot/Assets/en.lproj/Vector.strings
@@ -80,9 +80,13 @@
 "auth_missing_email" = "Missing email address";
 "auth_missing_phone" = "Missing phone number";
 "auth_missing_email_or_phone" = "Missing email address or phone number";
+"auth_email_in_use" = "This email address is already in use";
+"auth_phone_in_use" = "This phone number is already in use";
+"auth_untrusted_id_server" = "The identity server is not trusted";
 "auth_password_dont_match" = "Passwords don't match";
 "auth_username_in_use" = "Username in use";
 "auth_forgot_password" = "Forgot password?";
+"auth_email_not_found" = "Failed to send email: This email address was not found";
 "auth_use_server_options" = "Use custom server options (advanced)";
 "auth_email_validation_message" = "Please check your email to continue registration";
 "auth_msisdn_validation_title" = "Verification Pending";
diff --git a/Riot/ViewController/SettingsViewController.m b/Riot/ViewController/SettingsViewController.m
index 1cbbd1723..2cdc2e7b4 100644
--- a/Riot/ViewController/SettingsViewController.m
+++ b/Riot/ViewController/SettingsViewController.m
@@ -2884,6 +2884,36 @@ typedef void (^blockSettingsViewController_onReadyToDestroy)();
         [self stopActivityIndicator];
 
         NSLog(@"[SettingsViewController] Failed to request email token");
+        
+        // Translate the potential MX error.
+        MXError *mxError = [[MXError alloc] initWithNSError:error];
+        if (mxError && ([mxError.errcode isEqualToString:kMXErrCodeStringThreePIDInUse] || [mxError.errcode isEqualToString:kMXErrCodeStringServerNotTrusted]))
+        {
+            NSMutableDictionary *userInfo;
+            if (error.userInfo)
+            {
+                userInfo = [NSMutableDictionary dictionaryWithDictionary:error.userInfo];
+            }
+            else
+            {
+                userInfo = [NSMutableDictionary dictionary];
+            }
+            
+            userInfo[NSLocalizedFailureReasonErrorKey] = nil;
+            
+            if ([mxError.errcode isEqualToString:kMXErrCodeStringThreePIDInUse])
+            {
+                userInfo[NSLocalizedDescriptionKey] = NSLocalizedStringFromTable(@"auth_email_in_use", @"Vector", nil);
+                userInfo[@"error"] = NSLocalizedStringFromTable(@"auth_email_in_use", @"Vector", nil);
+            }
+            else
+            {
+                userInfo[NSLocalizedDescriptionKey] = NSLocalizedStringFromTable(@"auth_untrusted_id_server", @"Vector", nil);
+                userInfo[@"error"] = NSLocalizedStringFromTable(@"auth_untrusted_id_server", @"Vector", nil);
+            }
+            
+            error = [NSError errorWithDomain:error.domain code:error.code userInfo:userInfo];
+        }
 
         // Notify user
         [[NSNotificationCenter defaultCenter] postNotificationName:kMXKErrorNotification object:error];
@@ -2957,6 +2987,36 @@ typedef void (^blockSettingsViewController_onReadyToDestroy)();
         
         NSLog(@"[SettingsViewController] Failed to request msisdn token");
         
+        // Translate the potential MX error.
+        MXError *mxError = [[MXError alloc] initWithNSError:error];
+        if (mxError && ([mxError.errcode isEqualToString:kMXErrCodeStringThreePIDInUse] || [mxError.errcode isEqualToString:kMXErrCodeStringServerNotTrusted]))
+        {
+            NSMutableDictionary *userInfo;
+            if (error.userInfo)
+            {
+                userInfo = [NSMutableDictionary dictionaryWithDictionary:error.userInfo];
+            }
+            else
+            {
+                userInfo = [NSMutableDictionary dictionary];
+            }
+            
+            userInfo[NSLocalizedFailureReasonErrorKey] = nil;
+            
+            if ([mxError.errcode isEqualToString:kMXErrCodeStringThreePIDInUse])
+            {
+                userInfo[NSLocalizedDescriptionKey] = NSLocalizedStringFromTable(@"auth_phone_in_use", @"Vector", nil);
+                userInfo[@"error"] = NSLocalizedStringFromTable(@"auth_phone_in_use", @"Vector", nil);
+            }
+            else
+            {
+                userInfo[NSLocalizedDescriptionKey] = NSLocalizedStringFromTable(@"auth_untrusted_id_server", @"Vector", nil);
+                userInfo[@"error"] = NSLocalizedStringFromTable(@"auth_untrusted_id_server", @"Vector", nil);
+            }
+            
+            error = [NSError errorWithDomain:error.domain code:error.code userInfo:userInfo];
+        }
+        
         // Notify user
         [[NSNotificationCenter defaultCenter] postNotificationName:kMXKErrorNotification object:error];
         
diff --git a/Riot/Views/Authentication/AuthInputsView.m b/Riot/Views/Authentication/AuthInputsView.m
index b33b20cd8..6af7c8678 100644
--- a/Riot/Views/Authentication/AuthInputsView.m
+++ b/Riot/Views/Authentication/AuthInputsView.m
@@ -457,6 +457,36 @@
                                  return;
                              }
                              
+                             // Translate the potential MX error.
+                             MXError *mxError = [[MXError alloc] initWithNSError:error];
+                             if (mxError && ([mxError.errcode isEqualToString:kMXErrCodeStringThreePIDInUse] || [mxError.errcode isEqualToString:kMXErrCodeStringServerNotTrusted]))
+                             {
+                                 NSMutableDictionary *userInfo;
+                                 if (error.userInfo)
+                                 {
+                                     userInfo = [NSMutableDictionary dictionaryWithDictionary:error.userInfo];
+                                 }
+                                 else
+                                 {
+                                     userInfo = [NSMutableDictionary dictionary];
+                                 }
+                                 
+                                 userInfo[NSLocalizedFailureReasonErrorKey] = nil;
+                                 
+                                 if ([mxError.errcode isEqualToString:kMXErrCodeStringThreePIDInUse])
+                                 {
+                                     userInfo[NSLocalizedDescriptionKey] = NSLocalizedStringFromTable(@"auth_phone_in_use", @"Vector", nil);
+                                     userInfo[@"error"] = NSLocalizedStringFromTable(@"auth_phone_in_use", @"Vector", nil);
+                                 }
+                                 else
+                                 {
+                                     userInfo[NSLocalizedDescriptionKey] = NSLocalizedStringFromTable(@"auth_untrusted_id_server", @"Vector", nil);
+                                     userInfo[@"error"] = NSLocalizedStringFromTable(@"auth_untrusted_id_server", @"Vector", nil);
+                                 }
+                                 
+                                 error = [NSError errorWithDomain:error.domain code:error.code userInfo:userInfo];
+                             }
+                             
                              callback(nil, error);
                              
                          }];
@@ -530,6 +560,35 @@
                                  return;
                              }
                              
+                             // Translate the potential MX error.
+                             MXError *mxError = [[MXError alloc] initWithNSError:error];
+                             if (mxError && ([mxError.errcode isEqualToString:kMXErrCodeStringThreePIDInUse] || [mxError.errcode isEqualToString:kMXErrCodeStringServerNotTrusted]))
+                             {
+                                 NSMutableDictionary *userInfo;
+                                 if (error.userInfo)
+                                 {
+                                     userInfo = [NSMutableDictionary dictionaryWithDictionary:error.userInfo];
+                                 }
+                                 else
+                                 {
+                                     userInfo = [NSMutableDictionary dictionary];
+                                 }
+                                 
+                                 userInfo[NSLocalizedFailureReasonErrorKey] = nil;
+                                 
+                                 if ([mxError.errcode isEqualToString:kMXErrCodeStringThreePIDInUse])
+                                 {
+                                     userInfo[NSLocalizedDescriptionKey] = NSLocalizedStringFromTable(@"auth_email_in_use", @"Vector", nil);
+                                     userInfo[@"error"] = NSLocalizedStringFromTable(@"auth_email_in_use", @"Vector", nil);
+                                 }
+                                 else
+                                 {
+                                     userInfo[NSLocalizedDescriptionKey] = NSLocalizedStringFromTable(@"auth_untrusted_id_server", @"Vector", nil);
+                                     userInfo[@"error"] = NSLocalizedStringFromTable(@"auth_untrusted_id_server", @"Vector", nil);
+                                 }
+                                 
+                                 error = [NSError errorWithDomain:error.domain code:error.code userInfo:userInfo];
+                             }
                              callback(nil, error);
                              
                          }];
diff --git a/Riot/Views/Authentication/ForgotPasswordInputsView.m b/Riot/Views/Authentication/ForgotPasswordInputsView.m
index ec5f50ea6..18f4e6d35 100644
--- a/Riot/Views/Authentication/ForgotPasswordInputsView.m
+++ b/Riot/Views/Authentication/ForgotPasswordInputsView.m
@@ -251,7 +251,14 @@
                      }
                      
                      NSString *errorMessage;
-                     if (error.userInfo[@"error"])
+                     
+                     // Translate the potential MX error.
+                     MXError *mxError = [[MXError alloc] initWithNSError:error];
+                     if (mxError && [mxError.errcode isEqualToString:kMXErrCodeStringThreePIDNotFound])
+                         errorMessage = NSLocalizedStringFromTable(@"auth_email_not_found", @"Vector", nil);
+                     else if (mxError && [mxError.errcode isEqualToString:kMXErrCodeStringServerNotTrusted])
+                         errorMessage = NSLocalizedStringFromTable(@"auth_untrusted_id_server", @"Vector", nil);
+                     else if (error.userInfo[@"error"])
                          errorMessage = error.userInfo[@"error"];
                      else
                          errorMessage = error.localizedDescription;