Help! My original files are renamed to xx.jpg (NEF) during relocate originals...

Hi,

JUst updated to Ap 3.3.2 and started having this issue. All images from multiple camera (Nikon D800, Canon 100HS, and 300HS) imported properly into the Ap dB and displayes with original filenames. I relocated the originals to an external drive. Now, when I view the files on the external drive the filenames are all like this: <untitled> xx.nef/jpg/mov (for the appropriate file type). All files imported in the last two days are this way! When I view the files in Ap, they still maintain original filename. When I click "show in finder," the proper file is highlighted BUT has that funky <untitled> filename. Does anyopne know what is causing this? Also, how do I correct the filenames back to the opriginal filenames?

THANK YOU!