I have used Thunderbird as my email client for years. A while ago I noticed 'nstmp' folders that I did not create and that I can not get rid of. They are subfolders of the 'inbox' under 'Local Folders'. I tried deleting them in Thunderbird (right click, select delete) but that just gets the 'processing' circle of death. I tried deleting them from the program files for Thunderbird. No luck.

Any other suggestions? They do not affect the program but they annoy me and the number slowly grows. I just got a new computer and thought I would try to fix the problem one more time.