Fixing corrupted win2k registry with winXP 
Last week end a friend called me for help. The installed Windows 2000 showed a blue screen after boot saying that system32/config/software is no more readable. After some seconds system reboots again and again ending up at the blue screen.
This file is the windows registry containing HKEY_LOCALMASHINE/Software hive. Bad news. Without this hive all software settings are lost and you have to reinstall all kind of software. lucky who has a recent backup.
the backup we had was two years old. Worthless :(
Lookin around and searching the web many useless commercial tools came up. Most of them stating beeing capable of fixing corrupting files… But requiring a running system. What a heck..
at the end I came across a blog entry having the right answers .... unfortunately I lost the track and am not able to remember the URL. i would loved it to mention this fine dude.
the point is just boot a knoppix LiveCD , mount the filesystem and copy the file via FTP or another way to a mashine running Windows XP. winXP regedit is able to attach the file as a new hive. During loading it will detect that the file is corrupt and automatically recover it. A messagebox informs the user. Just copy the file back (do not forget to detach the hive from the registry7. and everything is fine again.
Yeah and do not forget a backup at least once aa month… you never know....