If you're getting the message "UPLOAD FAILED: AN UNKNOWN ERROR OCCURRED"
it means that a "time-out" or a "run-time" error has taken place.
Problems like that are usually due to either your ISP, YouTube,
or a network "hub-&-spoke" between the two that is attempting
to carry your uplink transmission to YouTube's Apache servers.
Another likely cause might be a weak/poor internet connection.
One thing you could do is press your "F5" key (or the "Refresh"
icon) and then try your upload again. Bear in mind though, that
your connection to YouTube needs to be smooth and constant
throughout the entire upload process (meaning no interruptions
or hiccups), otherwise everything will screw-up again and you'll
have to redo it all over. Thus, if you have a wireless connection,
make sure that it is seamless, strong, and without fluctuations.
You might want to try bypassing your router and putting a cord
from your computer directly to your modem.
There is also the possibility that you're unknowingly sending to
YouTube a bad, false or corrupted "cookie" or that maybe your
"cache" is full. Therefore...1) exit out of YouTube, 2) exit out of
your web browser, 3) reopen that web browser anew, 4) do one
of the sequences below, 5) then shutdown and reboot.
www . google . com / support / youtube / bin / answer . py ? hl = en & answer = 56120
http://www.google.com/support/youtube/bin/answer.py?hl=en&answer=56120
Internet Explorer 6:
→ Tools → Internet Options
→ Delete Cookies → OK
→ Delete Files → OK
→ Clear History → Yes
→ OK
Internet Explorer 7:
→ Tools → Internet Options → Delete...
→ Delete files → Yes
→ Delete cookies → OK
→ Delete history → OK
→ Close (browsing history window)
→ OK
Internet Explorer 8:
→ Tools → Delete Browsing History
[. ] Preserve Favorites (leave blank)
[x] Temporary Internet files
[x] Cookies
[x] History
→ Delete
Mozilla Firefox 3:
→ Tools → Clear Private Data
[x] Browsing History
[x] Download History
[x] Saved Form and Search History
[x] Cache
[x] Cookies
→ Clear Private Data Now
Mozilla Firefox 3.5:
→ Tools → Clear Recent History
Time range to clear: → Everything
▼ Details
[x] Browsing & Download History
[x] Saved Form and Search History
[x] Cookies
[x] Cache
→ Clear Now
Apple Safari 3:
→ Edit → Preferences
→ Security (tab) → Show Cookies
→ Remove All → Done
after that:
→ Safari → Empty Cache → Empty
after that:
→ History → Clear History
Google Chrome:
→ Tools (wrench) → Clear browsing data...
[x] Clear browsing history
[x] Clear download history
[x] Empty the cache
[x] Delete cookies
Clear data from this period: → Everything
→ Clear Browsing Data
Another possible cause of that dreaded "unknown error" is that
you may be doing other things on your computer while you are
uploading. This may cause all kinds of potential trouble as you
upload, particularly if you are websurfing or doing other internet
related things at the same time.