Unfortunately, all I'm getting when I upload an image on a test user is:
File is empty. Please upload something more substantial. This error could also be caused by uploads being disabled in your php.ini or by post_max_size being defined as smaller than upload_max_filesize in php.ini.
P.S That errors to just a page with the error, needing to hit Back on the Browser so that's not all that graceful and error message either.