I boot to the safe mode command prompt and run RSTRUI. Read http://support.microsoft.com/kb/304449
Thankfully I only need to type in RSTRUI and not that long path, but some have to do that.
I did a normal registry clean with a product I've used before, then I noticed things aren't working normally. So far, I'm missing media player, my DVD burner and player (still listed in hardware but exclamation marks) and System Restore. I restored from the Registry Cleaner backup file but I still can't access System Restore. I want to roll back to an earlier date. What other ways can I get to System Restore now?. It no longer opens from Help and support, or from accessories. I tried Safe Mode and Run,c:\windows\system32\restore\rstrui.exe. All I ever get is the hour glass for a couple of seconds. ANy ideas? I have a Sony Vaio XP Home.