I have CS6, 64-bit, and it has always worked fine. I have antivirus and antimalware that scan daily. The last few days PS has been doing strange things - I have always had zooming done with the scroll wheel and now it sometimes moves the image up and down, I always have the workspace set to have images floating and every few minutes it changes it. It has been doing a few other oddities off and on. I wish there were a way to run PS to repair but I don't think there is.