Index: openacs-4/packages/forums/lib/message/row.adp
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/forums/lib/message/row.adp,v
diff -u -r1.25 -r1.26
--- openacs-4/packages/forums/lib/message/row.adp	15 Jun 2018 20:50:33 -0000	1.25
+++ openacs-4/packages/forums/lib/message/row.adp	25 Jun 2018 09:15:00 -0000	1.26
@@ -27,9 +27,10 @@
       	  @message.user_name@
 	</if>
 	<else>
-	  <a href="user-history?user_id=@message.user_id@" title="#forums.show_posting_history_message_username#">
+	  <if @message.user_id;literal@ ne 0>
+              <a href="user-history?user_id=@message.user_id@" title="#forums.show_posting_history_message_username#"></if>
 	    @message.user_name@
-	  </a>
+	  <if @message.user_id;literal@ ne 0></a></if>
 	</else> #forums.on# <span class="post-date">@message.posting_date_pretty@</span>
   </div>
   </div>