It's been reported on these forums before that a corrupted video file can cause problems when Windows Explorer attempts to open the folder that contains the file.

This may be because, if the folder is set to Thumbnail view, Explorer tries to read part of the video file to display the video as a thumbnail.

You will need to find which file is corrupted and probably delete it. You can set any folder to display as a List or as Details, then in Folder Options under Tools in Windows Explorer select to display all folders the same way. That way, the error may not repeat when you try to open the folder.

I hope this helps.