Index: /trunk/src/VBox/VMM/HWACCM.cpp
===================================================================
--- /trunk/src/VBox/VMM/HWACCM.cpp	(revision 15933)
+++ /trunk/src/VBox/VMM/HWACCM.cpp	(revision 15934)
@@ -436,4 +436,9 @@
         LogRel(("HWACCM: No VMX or SVM CPU extension found. Reason %Rrc\n", pVM->hwaccm.s.lLastError));
         LogRel(("HWACCM: VMX MSR_IA32_FEATURE_CONTROL=%RX64\n", pVM->hwaccm.s.vmx.msr.feature_ctrl));
+        VMSetRuntimeError(pVM, false, "HwaccmDisabled",
+                         N_("You are trying to execute this VM with VT-x/AMD-V enabled but this hardware "
+                            "extension is either not available or it is disabled in the BIOS. You might "
+                            "check the BIOS settings and/or update the BIOS. The VM will be executed "
+                            "without using this hardware extension"));
 #ifdef RT_OS_DARWIN
         if (VMMIsHwVirtExtForced(pVM))