Question / Help OBS Recording And Windows Movie Maker

[DarkAzazel]

So I use OBS to stream and decided I wanted to use it for recording. Fraps is a pain in the ass and I feel like OBS is easier. So I did some recording and tried to open the .flv in Windows Movie Maker to do some editing. Windows Movie Maker wouldn't wouldn't recognize the file.
Basically, I just want to know if I'm doing anything wrong? Can I solve this?
Thanks for any help.