I have a fast 512 GB SSD C drive and a slower mechanical HD that I use for my data. The problem is that the hidden AppData folder is taking up almost 150 GB of my C drive. (It was 200 GB last week, not sure where the 50 GB went!) Is there any way to clean up this folder? Does CCleaner work on it? Is there another program that can help? When old programs are removed, are remnants in the AppData folder removed with it?