Why wont my video upload to youtube?

Have you actually saved your video as a video file yet, my friend, or is it still a project file? If it's got the suffix .mswmm then it's still a project file, which means that it's not yet a video. You need to click on File > Save Movie File ... or use the keyboard shortcut, Ctrl+P. This will save your video as a .wmv file, which you can upload to YouTube.com.

If you want to change the format, use the following website: http://www.onlinevideoconverter.com/ All you have to do once you get onto the site is click on the country you live in & then it will redirect you to a page. Click on "convert file from computer" (it should either say that or something similar to that) and then browse your computer for the file that you want to convert. Then pick the format you want to change it into (which is "WMV") & then click "Convert!" After it is complete, save it onto your computer again/save the changes. After that, try to upload it onto YouTube again. BUT, it may be that your video doesn't need format changing at all - you might have just saved it into the wrong place (trust me, I've been there!) Instead of saving it under "My Videos" - save it on your Desktop. Then try to upload it onto YouTube again. I hope this helps you! :]