To clean up your preview folder, you can use Windows Explorer to manually delete unwanted files. A more automated way is to:
- Download this file: Cleanup.txt.
- Place it on your desktop, or somewhere convenient.
- Rename it as Cleanup.bat
- Double click it whenever you need to delete the contents of your preview folder.
This is a little more involved than it needs to be. Files with a .bat extension are potential viruses, and this site's web-server will not send it directly to you with that extension. Following is the text from that file. You may prefer instead to paste this text into a file of the same name: