I recorded two tutorial videos using Hypercam, and then edited them with Windows Live Movie Maker, both of which exported "For High Definition Display"(or something like that), but when I uploaded them to YouTube, for some reason, one of them has HD up to 1080p, but one of them has no HD and only goes up to 360p, why is that?

NOTE: The video file itself, the one I uploaded to youtube, is in HD, so why isn't in HD on YouTube?