Folders On HDD Showing Up As Files/Cannot Access Files

Hey guys, I have a WD Passport (maybe 2 years old) that has about 900 gigs of files on it. Today I moved, then deleted around 72 gigs of stuff. After the delete, the finder seemed to hang so I relaunched the finder. After relaunch, the folders on the external drive show up as files. When I double click them they open, but do not show the files inside. I've deleted plists, repaired disk permissions, nothing. When I try to eject the drive it says a program is using it, but no program that I can find is actually using it. Any ideas?

I should also mention that I transferred files to the drive, the finder crashed and gave me error -50. Not sure what that is and can't find any documentation online...