What site are you trying to upload to?
Have you gone to Edit/Preferences and updated your web services?
Which antivirus and firewall are you using? Norton is notorious for blocking this sort of thing, and McAfee and Zone Alarm are nearly as bad.
Many posting on this forum have used the instructions at How can I get the best quality on YouTube? to improve their online video quality.
Insanity is hereditary, you get it from your children
I get three options to upload to (photohsop.com, YouTube and Podcast Hosting) and all three give me the same error message. I am running Security Essentials and the normal Win 7 firewall. Don't have Norton, McAfee or Zone Alarm. I went to Preferences and have web Services checked and also did a manual update Same error.
I go to Share, Online and select YouTube and when I select next the error appears