diff --git a/src/main/java/org/gcube/portlets/user/workspace/client/AppController.java b/src/main/java/org/gcube/portlets/user/workspace/client/AppController.java
index ab7b165..447a076 100644
--- a/src/main/java/org/gcube/portlets/user/workspace/client/AppController.java
+++ b/src/main/java/org/gcube/portlets/user/workspace/client/AppController.java
@@ -2060,7 +2060,7 @@ public class AppController implements SubscriberInterface {
 
 					@Override
 					public void onFailure(Throwable caught) {
-						Window.alert("error:  "+caught);
+						new MessageBoxAlert("Error", caught.getMessage(), null);
 					}
 
 					@Override
@@ -2142,7 +2142,7 @@ public class AppController implements SubscriberInterface {
 					@Override
 					public void onFailure(Throwable caught) {
 						fileVersioningEvent.getWinVersioning().unmask();
-						Window.alert("error:  "+caught);
+						new MessageBoxAlert("Error", caught.getMessage(), null);
 
 					}
 
@@ -2169,7 +2169,7 @@ public class AppController implements SubscriberInterface {
 					@Override
 					public void onFailure(Throwable caught) {
 						fileVersioningEvent.getWinVersioning().unmask();
-						Window.alert("error:  "+caught);
+						new MessageBoxAlert("Error", caught.getMessage(), null);
 
 					}