That's odd. Mind sharing the screenshot of the error message, we'd like to take a look. Also, clearing your browser's cache & cookies, clears things up on desktop and have you tried using another device/browser to see if that makes a difference? Keep us posted.
@YouTube @YTCreators @TeamYouTube why cant I upload? Everytime I try to upload a video today it says Unknown error?
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It has been fixed

the problem what ever it was fixed itself. Thanks tho! - 2 more replies
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