Geek Squad 4 GB USB Drive

[sillyfresh]

My friend just bought a usb drive and for some reason it is converting any file that is put on the drive to a .exe. I can't seem to figure our why it is doing this. I have reformatted it and looked for viruses on his comps but nothing has come up. Has anyone run into this type of issue or heard of this? Any help would be appreciated.