We're trying to post a Windows Movie Maker file, and the site says that .wmv, .mov, .avi, and .mpeg files will work.
The video doesn't have a file like that, it just says "Windows Movie Maker."
Do you know how to make a Windows Movie Maker file into one of the supported files?
The file was likely a .MSWMM file--which seems to mean "Microsoft Windows Movie Maker." That means that it's a project file, and not a movie. And there's a big difference between a project file and an actual media file.
A project file is basically a fancy spreadsheet that says, "At this moment, play this clip. At this moment, show this picture. From here to there, play this song" ...and on and on it goes. So a project file doesn't actually have any media in it... which is why project files are relatively small.
A media file contains all the information needed for a computer to play back your media. These are much bigger.
So, if you want to share your media with someone else, you need to make sure you have a media file and not just a project file.
This kind of mistake is actually quite common. For example, I've had people hand me an .html document for a website they were designing on their home computer and were shocked that I couldn't look at it for them. "It works on my computer," they insist.
Yes, but my computer doesn't have all the media files you were linking to on your hard drive. A related mistake is when people post a link to a file on their hard drive: c:\user\luke\documents\My Scrip.rtf. Since it's on your hard drive, I can't look at it. It needs to be online.
If you make this mistake, it's not a big deal. Sending a project file instead of a media is much like sending an email and forgetting the attachment. You're telling someone that the media is there... you're just not giving it to them.
Your Media Production Mentor