I run Win7 Pro (x64) and downloaded ccleaner v3.12.1572 (x64) from Filehippo.com yesterday.I ran the ccleaner X64 and then tried to run FSX and the FSX splash screen just hung with the mouse circle spinning. I have a baseline image for my drives but, had forgotten to back up my rewards/flights and just restarted those over again. I didn't know what caused the first hangup..so after the second install and after getting the "beginner" rewards back, I closed up shop for the night. I ran the ccleaner again this morning and AGAIN it hung up the FSX program on the splash screen.Of course I'm going to back up my flightlog, flightplans and rewards before I re-image for the 2nd time and then go back to using the ccleaner x32 as I don't recall it giving me any problems before.