Data Execution Prevention error

XP Pro SP2... I have a folder that contains maybe 6 or 7 folders, and each folder contains anywhere from 1 to 4 .avi files. I can browse thru everything OK except for one of the folders. As soon as I open the folder, I get a DEP error, which in turn causes a Windows Explorer error. I've attached screenshots below. This only happens when browsing the one folder. The errors come up before I even get a chance to play one of the .avi files. The same thing has happened on an external USB drive that has a bunch of .avi files on it. All malware scans come up clean. Any ideas?
Thanks.

 

Seems a strange problem, these folders are located on your hard drive or a network?
Have you tried copying the folders to another location on your computer and then opening?

 

The folder is on C: drive. In it there are 5 or 6 folders, and each has some .avi's in it. Only one of the 5 or 6 folders causes the error right when I open it. I don't even get a chance to try to play the .avi. I also have a USB external drive (also with lots of avi files) that more or less does the same thing, but I'm not too worried about the USB drive right now.