Index: /trunk/src/VBox/Devices/Storage/DrvHostBase-win.cpp
===================================================================
--- /trunk/src/VBox/Devices/Storage/DrvHostBase-win.cpp	(revision 66075)
+++ /trunk/src/VBox/Devices/Storage/DrvHostBase-win.cpp	(revision 66076)
@@ -565,6 +565,6 @@
         do
         {
-            if (pThis->hwndDeviceChange)
-                PostMessage(pThis->hwndDeviceChange, WM_CLOSE, 0, 0); /* default win proc will destroy the window */
+            if (pThis->Os.hwndDeviceChange)
+                PostMessage(pThis->Os.hwndDeviceChange, WM_CLOSE, 0, 0); /* default win proc will destroy the window */
 
             rc = RTThreadWait(pThis->Os.hThrdMediaChange, 100, NULL);