Have you taken a look at this troubleshooter yet: https://goo.gl/Q9UCB8 ? The troubleshooting guide covers common uploading errors and how to fix them.
@TeamYouTube Why isn't your site letting me upload video, all my network connection is working fine???pic.twitter.com/0CHlD07nrO
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Thanks. Twitter will use this to make your timeline better. UndoUndo
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