I’ve got to handle it to Oracle; their virtualization software VirtualBox is amazing…and free! It’s features surpass Windows Virtual PC by leaps and are on par with VMWare Workstation. Lately I have been using it for all my host-based virtualization needs.

I am in the process of setting up a new computer and part of that means moving all my VMs. I use the export and then import feature in VirtualBox to do this. After I moved a Windows XP machine it would not boot on the new PC, and kept bluescreening continuously. This was the error:

DRIVER_UNLOADED_WITHOUT_CANCELLING_PENDING_OPERATIONS caused by intelppm.sys.

After a brief Google search I turned up this post by Ben Armstrong (Virtual PC Guy) from the Microsoft virtualization team:http://blogs.msdn.com/b/virtual_pc_guy/archive/2005/10/25/problems-with-intelppm-sys-and-processr-sys-under-virtual-pc-virtual-server.aspx

According to Ben this driver; intelppm.sys, processr.sys and perhaps also p3.sys can cause problems when they try to do something that is not supported by the hypervisor. Apparently the problem affects Microsoft products such as Virtual PC and Virtual Server as well. There is also a ticket logged for VirtualBox regarding this issue: http://www.virtualbox.org/ticket/420

The solution is to boot into Safe Mode (F8 during start up) and entering one or more of these commands, depending on which driver is causing the issue:

• sc config p3 start= disabled
• sc config intelppm start= disabled
• sc config processr= disabled

You could also follow the instructions in Ben’s post and do these changes manually in the Registry.