I can't add videos to iTunes

I'm running iTunes 10.7 on Windows XP and am trying to add my video collection to iTunes. I'm currently trying to add videos from an external hard drive to my iTunes library. When I drag and drop files onto the library it highlights the sidebar and turns blue, but then never imports it. I've also tried using to "Add a file" button with no success. Importing music works just swimmingly. All Videos are .m4v format bought off of iTunes on my account, which my computer has been authorized to use.

Any help in resolving this issue would be greatly appreciated!