Index: /trunk/src/VBox/Frontends/VirtualBox/src/runtime/UISession.cpp
===================================================================
--- /trunk/src/VBox/Frontends/VirtualBox/src/runtime/UISession.cpp	(revision 27477)
+++ /trunk/src/VBox/Frontends/VirtualBox/src/runtime/UISession.cpp	(revision 27478)
@@ -614,4 +614,8 @@
     }
 
+    /* Guard progressbar warnings from auto-closing: */
+    if (uimachine()->machineLogic())
+        uimachine()->machineLogic()->setPreventAutoClose(true);
+
     /* Show "Starting/Restoring" progress dialog: */
     if (isSaved())
@@ -619,4 +623,8 @@
     else
         vboxProblem().showModalProgressDialog(progress, machine.GetName(), mainMachineWindow());
+
+    /* Allow further auto-closing: */
+    if (uimachine()->machineLogic())
+        uimachine()->machineLogic()->setPreventAutoClose(false);
 
     /* Check for a progress failure: */