Index: /trunk/src/VBox/Frontends/VirtualBox/src/VBoxFBOverlay.cpp
===================================================================
--- /trunk/src/VBox/Frontends/VirtualBox/src/VBoxFBOverlay.cpp	(revision 23680)
+++ /trunk/src/VBox/Frontends/VirtualBox/src/VBoxFBOverlay.cpp	(revision 23681)
@@ -719,4 +719,10 @@
             str = glGetString(GL_VERSION);
             );
+
+    if(!str)
+    {
+        VBOXQGLLOGREL (("failed to make the context current, treating as unsupported\n"));
+        return;
+    }
 
     VBOXQGLLOGREL (("gl version string: 0%s\n", str));