I use Windows 7 Virtual PC on my current project and I often bring home the files, so I can work some in the evenings. Since my VHDs are large, I’ll only copy the undo disks, saved state, and virtual machine config files from my external drive. I copy them to a small portable drive and once I get home, I’ll copy them to a large external drive.
I’ve done this for over a year, but recently I started getting an error when I tried to start the VPC after the copying was finished. It would open the initial window with the progress bar, but eventually the bar would stop, turn red, and then the error “RPC server unavailable” would appear. When I first started seeing these, I’d try again, but no luck.
After some testing, it turns out that my small portable drive is apparently going bad, so it was corrupting the files. Lucky for me, that I never overwrote my good copies with corrupted copies, at least not at both the office and at home.