Parallels crashed on me this afternoon while Windows was installing patches and rebooting. When I tried to start the system up again I kept getting this error message:

Parallels Desktop is unable to access the virtual hard disk image file winxp3.hdd. The file is missing, corrupted, or used by other application.

I knew that the file wasn’t in use by any other application because Parallels was no longer running and I had rebooted my machine.

It took a bit of digging, but here is how to make it stop thinking the file is in use:

- Locate your .hdd file (usually in ~/Library/Parallels)
- Right click on the file and choose “Show Package Contents”

When the package is opened, look for a file called “DiskDescriptor.xml.lck”. This is the file it uses to determine if the disk image is in use. Toss this file in the trash and close the package. Parallels should now start up.

Of course, as soon as I post about my OSX kernel panics being fixed, there it is again. This definitely has something to do with networking, but it is tough to tell with all the layers.

I am using:

• WiFi (with patched 802.11n firmware)
• Wired Ethernet
• Tunnelblick (OpenVPN)
• Parallels Shared Networking

The crash always seems to occur, but not consistently:

• When switching from WiFi to Ethernet, or the other way around
• When Tunnelblick connection is dropped unexpectedly
• When switching from shared to host only networking in Parallels

I am going to try my best to recreate the issue consistently soon and be done with it for good.

Update (1/30/2008):
Upgrading my version of Parallels to 3.0, build 5582 has fully fixed the problem once and for all. It has now been over 30 days without a Kernel Panic!