Anyone else having problems uploading videos? Need some help.

[BUZ]

Today I went to upload a video on photobucket (around 10mb) and for some reason it gets stuck around 50% and will not upload beyond that that. About twenty seconds into the video loading a box pops up (see pic below), does this on youtube also. Anyone run into this problem and know of a fix, been going at it for about two hours now and cannot find anything. Have uploaded dozens of videos in the past and never once had a single issue.

Using vista/firefox BTW.