During a normal server maintenance period I had an unfortunate incident where one of the virtual machines I was patching simply disappeared.
Needless to say I started to panic! I didn’t quite understand how a virtual machine could simply go missing. I checked and verified that the VHD and config file were still there and in the appropriate places.
I did some digging around until I came upon an elusive blog where the guy had mentioned fixing an extra character in the config file. It turns out that there is a little known bug in 2008 R2 Hyper-V where the xml config files would get an extra character or two when deleting a snapshot or making any routine changes.
I went through the entire configuration file until I saw the issue. At the very end, there was an extra “>” bracket! I deleted it and restarted the Hyper-V Management. Then the VM that magically vanished, just showed up like nothing ever happened.