Index: messageforums-app/src/java/org/sakaiproject/tool/messageforums/DiscussionForumTool.java
===================================================================
--- messageforums-app/src/java/org/sakaiproject/tool/messageforums/DiscussionForumTool.java	(revision 2631)
+++ messageforums-app/src/java/org/sakaiproject/tool/messageforums/DiscussionForumTool.java	(working copy)
@@ -2722,7 +2722,7 @@
     String redirectTo = getExternalParameterByKey(REDIRECT_PROCESS_ACTION);
     String expand = getExternalParameterByKey("composeExpand");
 
-    if (redirectTo == null)
+    if (redirectTo == null || selectedTopic == null)
     {
       return gotoMain();
     }