Index: /trunk/src/VBox/Additions/common/VBoxService/VBoxServiceControlExecThread.cpp
===================================================================
--- /trunk/src/VBox/Additions/common/VBoxService/VBoxServiceControlExecThread.cpp	(revision 38865)
+++ /trunk/src/VBox/Additions/common/VBoxService/VBoxServiceControlExecThread.cpp	(revision 38866)
@@ -339,8 +339,8 @@
     if (RT_SUCCESS(rc))
     {
-        const PVBOXSERVICECTRLTHREAD pNode = vboxServiceControlExecThreadGetByPID(uPID);
-        if (pNode)
-        {
-            const PVBOXSERVICECTRLTHREADDATAEXEC pData = (PVBOXSERVICECTRLTHREADDATAEXEC)pNode->pvData;
+        const PVBOXSERVICECTRLTHREAD pThread = vboxServiceControlExecThreadGetByPID(uPID);
+        if (pThread)
+        {
+            const PVBOXSERVICECTRLTHREADDATAEXEC pData = (PVBOXSERVICECTRLTHREADDATAEXEC)pThread->pvData;
             AssertPtr(pData);
 
@@ -353,9 +353,7 @@
 
                 case OUTPUT_HANDLE_ID_STDOUT: /* StdOut */
+                default: /* On VBox host < 4.1 this is 0, so default to stdout
+                          * to not break things. */
                     pPipeBuf = &pData->stdOut;
-                    break;
-
-                default:
-                    AssertReleaseMsgFailed(("Unknown output handle ID (%u)\n", uHandleId));
                     break;
             }