diff --git a/dsf/org.eclipse.cdt.dsf/src/org/eclipse/cdt/dsf/debug/sourcelookup/DsfSourceLookupParticipant.java b/dsf/org.eclipse.cdt.dsf/src/org/eclipse/cdt/dsf/debug/sourcelookup/DsfSourceLookupParticipant.java
index 0e9edb7f242..b3c2afda38a 100644
--- a/dsf/org.eclipse.cdt.dsf/src/org/eclipse/cdt/dsf/debug/sourcelookup/DsfSourceLookupParticipant.java
+++ b/dsf/org.eclipse.cdt.dsf/src/org/eclipse/cdt/dsf/debug/sourcelookup/DsfSourceLookupParticipant.java
@@ -191,7 +191,7 @@ public class DsfSourceLookupParticipant implements ISourceLookupParticipant {
 		if ( !(object instanceof IDMContext) || 
              !((IDMContext)object).getSessionId().equals(fSessionId) ) 
         {
-            throw new CoreException(new Status(IStatus.ERROR, DsfPlugin.PLUGIN_ID, -1, "Invalid object", null)); //$NON-NLS-1$
+            return null;
         }
         
         final IDMContext dmc = (IDMContext)object;