Please run this program from the Administrator account so it can set up your license. Once the license is set up, you can run it from any account.
Now, before someone says "Download something better", I plan to, however, I like WMP itself for certain things, and I want it fixed. My desktop account IS an administrator by the way. I rightclick WMP, run it as Administrator, and it runs it fine, but that is the only way I can play it there, is by "run as administrator"ing it. It only happens on new videos I make, even if I oversave it. It was once working fine, but once I restored my computer, it started happening. I am on Windows 7, not 100% sure, but I think WMP is WMP10.