I installed Returnil last year during one of their promos... BUT one day when I tried to turn on "Safe Mode" it refused to enter it.

I posted to their forum, e-mailed Tech Support and never got any answer. Finally, I got fed up and uninstalled it via Revo Uninstaller. I'm done with Returnil.

I have all my data on a second partition and regularly make images of my system partition. (When the image files are less than 10 GB, you can easily do that monthly and archive to external HD or DVD.)

I've tried Wise Registry Cleaner and I like it. I heard about it
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where the Ashraf's colleague says he uses CCleaner, Glary Utilities, and Wise Registry Cleaner in that order. (With Wise, choose only those marked as "Safe" to fix.)

I also employ jv16 PowerTools 2010 as a 4th step. By the time I get to jv16, there are very few "bad" reg entries left. But each program picks up a couple the others don't. Of course, I keep backups for each step... just in case. And then I use the system for several days before I relax. So, far so good.

Main reason I use those is to remove any crap that Revo Uninstaller misses.

And I really should tweak my Sandboxie setup and use it regularly.