Strange thing on Windows Media Player 10

First off I want to thank "The MC" for helping me out with my last problem. Worked well enough (even when I screwed up in the process), and now things are back to normal. However, my Media Player is doing something funny, now. It won't go to "Full Screen" with a movie file, and it doesn't matter what type the file is. It just gives me the all-too familiar "Would you like to send an error report?" pop-up and then it closes. It works fine otherwise. Anyone know why this is? Do I need some sort of plug-in? Thanks in advance.

 

media player 10 has given me so many problems that i went back to player 9 - so much easier and user-friendly i found.
but, when i had a few problems, i tried reinstalling a few times and the problems were long gone, try it and see if the problem persists...