Booting Windows XP on different disk controller

So you made a virtual machine from the real one with disk2vhd (see previous blog) and now you try to run it inside VirtualBox (or another virtual PC engine) but all you get is a BSOD during the boot? With the error code 7b? The problem is in the disk controller driver - the old machine had a different one that the new has. The solution is to force Windows to use "default" disk drivers. All it requires is a registry hack that is explained here: http://www.biermann.org/philipp/STOP_0x0000007B/
There is also another option if you can boot (WinPE, Winternals ERD etc.)into doomed Windows XP - replace the aaaa\ with SYSTEM\ in the merge reg file and apply it with double clicking (or import in regedit).