Windows 7 thumbnail problems

Okay, I've only been having this problem on my Windows 7 computer. Every so often, about once every couple of weeks, my thumbnails all delete. I'll go into into my picture folder and they're all just the basic JPG symbol or whatever file type it is. Even the folder thumbnail itself just shows a basic file without the little sub-folders or mini-picture thumbnails inside like normal. Now, they all reload and work just fine after that, so it's not a HUGE problem, but some of my folders take a while to load all of the thumbnails. It's just really annoying because I have to re-load all of my folder's thumbnails again every couple of weeks and just... ugh. I just want them to always be there and stop deleting! I have too many folders to keep having to reload all of the thumbnails inside :mad Yes, I'm a little bit OCD lol.

 

You mean doing a Disc Cleanup right? Because I make a point of un-checking "thumbnails" when I do that. So unless I have to do something else than just un-checking that selection, they shouldn't be getting deleted from that. Or maybe you meant a different kind of cleaning?

 

Well like I said, I go out of my way to not delete my thumbnails when I do computer cleans. It never occurs after I run something like that, so I don't think it's accidental, because it always happens randomly. I'll be on the computer for a few hours and everything's fine, then I'll close a folder, open a new one, and now randomly the thumbnails are just gone. It really makes no sense. I mean unless running my anti-virus or something deleted all of my thumbnails somehow, but it took 5 hours to register in the computer that they were gone...