diff --git a/mindplot/src/main/javascript/RestPersistenceManager.js b/mindplot/src/main/javascript/RestPersistenceManager.js
index dc72e303..66785cea 100644
--- a/mindplot/src/main/javascript/RestPersistenceManager.js
+++ b/mindplot/src/main/javascript/RestPersistenceManager.js
@@ -65,7 +65,7 @@ mindplot.RESTPersistenceManager = new Class({
                 onFailure:function (xhr) {
 
                     var responseText = xhr.responseText;
-                    var userMsg = {severity:"ERROR", message:$msg('SAVE_COULD_NOT_BE_COMPLETED')};
+                    var userMsg = {severity:"SEVERE", message:$msg('SAVE_COULD_NOT_BE_COMPLETED')};
 
                     var contentType = this.getHeader("Content-Type");
                     if (contentType != null && contentType.indexOf("application/json") != -1) {
@@ -80,7 +80,7 @@ mindplot.RESTPersistenceManager = new Class({
 
                     } else {
                         if (this.status == 405) {
-                            userMsg = {severity:"ERROR", message:$msg('SESSION_EXPIRED')};
+                            userMsg = {severity:"SEVERE", message:$msg('SESSION_EXPIRED')};
                         }
                     }
                     events.onError(userMsg);
diff --git a/wise-webapp/src/main/java/com/wisemapping/rest/BaseController.java b/wise-webapp/src/main/java/com/wisemapping/rest/BaseController.java
index 96f77058..37d7ec87 100644
--- a/wise-webapp/src/main/java/com/wisemapping/rest/BaseController.java
+++ b/wise-webapp/src/main/java/com/wisemapping/rest/BaseController.java
@@ -63,20 +63,20 @@ public class BaseController {
     @ExceptionHandler(Exception.class)
     @ResponseStatus(HttpStatus.INTERNAL_SERVER_ERROR)
     @ResponseBody
-    public String handleServerErrors(@NotNull Exception ex, @NotNull HttpServletRequest request) {
+    public RestErrors handleServerErrors(@NotNull Exception ex, @NotNull HttpServletRequest request) {
         final User user = Utils.getUser();
         notificationService.reportJavaException(ex, user, request);
-        return ex.getMessage();
+        return new RestErrors(ex.getMessage(),Severity.SEVERE);
     }
 
 
     @ExceptionHandler(ImportUnexpectedException.class)
     @ResponseStatus(HttpStatus.INTERNAL_SERVER_ERROR)
     @ResponseBody
-    public String handleImportErrors(@NotNull ImportUnexpectedException ex, @NotNull HttpServletRequest request) {
+    public RestErrors handleImportErrors(@NotNull ImportUnexpectedException ex, @NotNull HttpServletRequest request) {
         final User user = Utils.getUser();
         notificationService.reportJavaException(ex, user, new String(ex.getFreemindXml()), request);
-        return ex.getMessage();
+        return new RestErrors(ex.getMessage(),Severity.SEVERE);
     }
 
     @ExceptionHandler(ValidationException.class)
@@ -87,8 +87,8 @@ public class BaseController {
 
     @ExceptionHandler(JsonHttpMessageNotReadableException.class)
     @ResponseStatus(HttpStatus.BAD_REQUEST)
-    public String handleJSONErrors(@NotNull JsonHttpMessageNotReadableException ex) {
-        return "Request could not be saved. Message is not valid";
+    public RestErrors handleJSONErrors(@NotNull JsonHttpMessageNotReadableException ex) {
+        return new RestErrors("Communication error",Severity.SEVERE);
     }
 
     @ExceptionHandler(java.lang.reflect.UndeclaredThrowableException.class)