CCleaner Registry Problem

I just downloaded CCleaner and was attempting to clean my registry. It runs briefly until the bar at the top reaches 4% and then it stops. Even after waiting 5 minutes, the bar remains at 4%. Any ideas as to what I should do? Am I being impatient or is the program not operating properly?

Thanks

MacMck

What's your OS ? XP, Vista, 7 ?

Is it 64-bit ?

This previous thread on the same problem may be of some use:

http://forum.piriform.com/index.php?showtopic=25446

Important of course to answer Aethec's querie re your specs, but I may not be on here for a few days so for that reason I'm posting it now.