diff --git a/src/osgViewer/Viewer.cpp b/src/osgViewer/Viewer.cpp
index 5f1e76524..4d9e4d822 100644
--- a/src/osgViewer/Viewer.cpp
+++ b/src/osgViewer/Viewer.cpp
@@ -2017,6 +2017,7 @@ void Viewer::eventTraversal()
                         if (wasThreading) stopThreading();
                         
                         gw->close();
+                        _currentContext = NULL; 
                         
                         if (wasThreading) startThreading();