howdy - a quick guess is that the pool sites don't like the wmv format even though they claim to accept it. There are different versions of wmv and some of them might give the site fits when it tries to process (convert?) it. Having hassled with wmv conversion in the past I know it's one of the more troublesome formats to mess with.
One possible fix might be to convert to a format they like.
Another idea is that they don't like an irregular size. The video should be 320 x 240 or 640 x 480 resolution. Larger than that is unusual.
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Without getting too technical, there are 3 formats I'd recommend:
1. mp4 using divx video and mp3 audio (from the youtube faq on recommended video uploading... might not apply to other video sites, but I think your odds with this one are good)
2. AVI using same, or mpeg (pretty much guaranteed to work, as these formats are super common and easy to convert/manipulate... only downside is that the filesize may be larger so the upload might take even longer)
3. flv format - this is pretty much the native format of youtube and google videos, and also happens to be very good in terms of compression/quality, so I'd think it'd be a good solution too.
To convert fairly easily to any of these 3 options, the most straightforward program is called "super". You may never end up trying this but I'll do a mini-walkthrough anyway:
Drag and drop your wmv (or whatever) movie to the bottom. For the first dropdown choose mp4, avi, mpg (MPEG II), or swf/flv. What you choose in the first dropdown determines what's available in the next one... video codec. Here choose divx for the first two options, and the other 2 are self explanatory. For audio choose mp3 if it's available, AAC if not. You can also see where you can set the resolution and change the bitrate, which affects the final quality/filesize. 720's a fair bitrate. I wouldn't fool with any other settings except perhaps to check the "Directshow decode" box, which you want to do if you ever installed ffdshow on your computer.
ctrl+T to choose where you want to save converted files, and then click "encode active files" to get the conversion going. Once it's done try uploading your converted file and let us know if you had any luck.
Looking forward to watching!
PS: since super's official webpage is quite ghetto and makes it hard to find the actual (free) download, I uploaded the installer here:
http://creedo.gbgl-hq.com/SUPERsetupJan18.exe
It's about 27 megs.