Index: /trunk/src/VBox/Main/src-client/GuestCtrlImpl.cpp
===================================================================
--- /trunk/src/VBox/Main/src-client/GuestCtrlImpl.cpp	(revision 48341)
+++ /trunk/src/VBox/Main/src-client/GuestCtrlImpl.cpp	(revision 48342)
@@ -97,7 +97,5 @@
     uint32_t uContextID;
     int rc = pSvcCb->mpaParms[0].getUInt32(&uContextID);
-    AssertMsgRC(rc, ("Unable to extract callback context ID, pvData=%p\n", pSvcCb));
-    if (RT_FAILURE(rc))
-        return rc;
+    AssertMsgRCReturn(rc, ("Unable to extract callback context ID, pvData=%p\n", pSvcCb), rc);
 #ifdef DEBUG
     LogFlowFunc(("CID=%RU32, uSession=%RU32, uObject=%RU32, uCount=%RU32\n",
Index: /trunk/src/VBox/Main/src-client/GuestSessionImpl.cpp
===================================================================
--- /trunk/src/VBox/Main/src-client/GuestSessionImpl.cpp	(revision 48341)
+++ /trunk/src/VBox/Main/src-client/GuestSessionImpl.cpp	(revision 48342)
@@ -1317,11 +1317,11 @@
     CALLBACKDATA_SESSION_NOTIFY dataCb;
     /* pSvcCb->mpaParms[0] always contains the context ID. */
-    pSvcCbData->mpaParms[1].getUInt32(&dataCb.uType);
-    pSvcCbData->mpaParms[2].getUInt32(&dataCb.uResult);
+    int vrc = pSvcCbData->mpaParms[1].getUInt32(&dataCb.uType);
+    AssertRCReturn(vrc, vrc);
+    vrc = pSvcCbData->mpaParms[2].getUInt32(&dataCb.uResult);
+    AssertRCReturn(vrc, vrc);
 
     LogFlowThisFunc(("ID=%RU32, uType=%RU32, guestRc=%Rrc\n",
                      mData.mSession.mID, dataCb.uType, dataCb.uResult));
-
-    int vrc = VINF_SUCCESS;
 
     GuestSessionStatus_T sessionStatus = GuestSessionStatus_Undefined;