Index: /trunk/src/VBox/HostServices/GuestProperties/service.cpp
===================================================================
--- /trunk/src/VBox/HostServices/GuestProperties/service.cpp	(revision 58774)
+++ /trunk/src/VBox/HostServices/GuestProperties/service.cpp	(revision 58775)
@@ -1561,5 +1561,5 @@
                             0 /* default stack size */,
                             RTTHREADTYPE_DEFAULT,
-                            0, /* no flags. */
+                            RTTHREADFLAGS_WAITABLE,
                             "GSTPROPNTFY");
     }
@@ -1588,5 +1588,6 @@
         if (RT_SUCCESS(rc))
             RTReqRelease(pReq);
-
+        rc = RTThreadWait(mhThreadNotifyHost, 1000, NULL);
+        AssertRC(rc);
         rc = RTReqQueueDestroy(mhReqQNotifyHost);
         AssertRC(rc);