I use win_xp_sp3 inside my virtualbox i was mapped all the xp folder destination into my host machine in regedit. and now i need to change the my username and i don't remember all files i changed. is there any possibility on regedit find and replace?
There are a few free tools out there for example:
Just remember to backup your registry before you do anything :)
Something like ERUNT should be good for the backup.