Index: /trunk/src/VBox/Additions/WINNT/Graphics/Video/disp/wddm/VBoxDispCm.cpp
===================================================================
--- /trunk/src/VBox/Additions/WINNT/Graphics/Video/disp/wddm/VBoxDispCm.cpp	(revision 45402)
+++ /trunk/src/VBox/Additions/WINNT/Graphics/Video/disp/wddm/VBoxDispCm.cpp	(revision 45403)
@@ -207,8 +207,19 @@
 
     pCmd->EscapeHdr.escapeCode = VBOXESC_GETVBOXVIDEOCMCMD;
+
+    PVBOXWDDMDISP_CONTEXT pContext = NULL, pCurCtx;
+
     /* lock to ensure the context is not destroyed */
     EnterCriticalSection(&pSession->CritSect);
     /* use any context for identifying the kernel CmSession. We're using the first one */
-    PVBOXWDDMDISP_CONTEXT pContext = RTListGetFirst(&pSession->CtxList, VBOXWDDMDISP_CONTEXT, ListNode);
+    RTListForEach(&pSession->CtxList, pCurCtx, VBOXWDDMDISP_CONTEXT, ListNode)
+    {
+        PVBOXWDDMDISP_DEVICE pDevice = pCurCtx->pDevice;
+        if (VBOXDISPMODE_IS_3D(pDevice->pAdapter))
+        {
+            pContext = pCurCtx;
+            break;
+        }
+    }
     if (pContext)
     {
Index: /trunk/src/VBox/Additions/WINNT/Graphics/Video/mp/wddm/VBoxMPWddm.cpp
===================================================================
--- /trunk/src/VBox/Additions/WINNT/Graphics/Video/mp/wddm/VBoxMPWddm.cpp	(revision 45402)
+++ /trunk/src/VBox/Additions/WINNT/Graphics/Video/mp/wddm/VBoxMPWddm.cpp	(revision 45403)
@@ -4024,6 +4024,14 @@
                 if (pEscape->PrivateDriverDataSize >= sizeof (VBOXDISPIFESCAPE_GETVBOXVIDEOCMCMD))
                 {
-                    Status = vboxVideoCmEscape(&pContext->CmContext, pRegions, pEscape->PrivateDriverDataSize);
-                    Assert(Status == STATUS_SUCCESS);
+                    if (pContext->enmType == VBOXWDDM_CONTEXT_TYPE_CUSTOM_3D)
+                    {
+                        Status = vboxVideoCmEscape(&pContext->CmContext, pRegions, pEscape->PrivateDriverDataSize);
+                        Assert(Status == STATUS_SUCCESS);
+                    }
+                    else
+                    {
+                        WARN(("VBOXESC_GETVBOXVIDEOCMCMD recieved invalid context type %d", pContext->enmType));
+                        Status = STATUS_INVALID_PARAMETER;
+                    }
                 }
                 else