Before you Edit the Registry
Entire backup: One little slip in editing the Registry can result in disaster. You might do anything from introducing trouble to making Windows unable to start.
If you have done much work with Windows -- updating, changing settings, installing hardware or programs -- since you last backed up the the Registry, back up the entire Registry before you start editing!
Incremental backup: Always back up at least the key you intend to edit before you start.
Be on Guard:
If you suspect something has gone horribly wrong -- you've lost a key, something no longer works or Windows crashes -- do not attempt to restart Windows in normal mode. Start in "safe mode" (hold down the F8 key just at the point where Windows starts to load). Otherwise Windows will over-write the "last known good" configuration in attempting to start.
