What do you do when the registry of a Windows 2000 system is destroyed, so the system doesn't even start any more?
A small note, which however may be "life-saving": It occurs sometimes (particularly under PCU stress) that one calls a Setup program (many of these installation programs run in the 16-Bit subsystem) and it simply does not start. It's no problem to end off the appropriate process (wowexec.exe) in the task manager or when shutting the computer down - however caution: it occurred to me twice in such cases that files absolutely necessary for the system to start irrevocably damaged by "shooting off" such a 16-bit process. The system didn't even start afterwards. A complete new installation of all programs is more than annoying and costs a bunch of time. The most critical files (registry) can be found in the directory WinntSystem32Config; however, the system doesn't even permit reading access to them during operation. Thus, what do you do?
The NT Backup program (WinntSystem32NTBackup.exe) offers a way out. Having started it in the menu "Extra" you find the possibility of creating an emergency disk. If one calls this point, one has the option of backing up the registry - the critical files afterwards are located in the directory WinntRepairRegBack.
In the worst case, you can boot from the installation CD and choose the option "Repair", namely into the recovery console. There, some of the well-known DOS prompt commands are available -- among other things the saving "copy". After manual copying of the backup from the RegBack into the Config directory the system restarted without problems and everything worked fine again. Of course it is mandatory to have a recent backup; thus this should be done at least once a week.
A more professional approach to this problem is the program "O&O Bluecon" (www.oo-software.de), which gives the option to do such a backup during every start and keep a number of backups that can be specified by the user. However, this solution costs some bucks, of course.