Camtasia 8 Import WMV Codec Error?

Hey guys, I'm trying to get some WMV files into Camtasia 8 to edit them before I put them back on YouTube, problem is they won't import. Any one know a way around this? I initially tried MP4's that didn't work, so I converted them all, and the first WMV worked but all my other ones won't for some reason.

It's a software issue I have the same problem on one of my laptops it doesn't like mp4 file and crashes all the time when I'm just moving things around
It's works perfectly on my other Dell for unknown reasons