I too had this problem, read the forum and found it was the windows hotifx doing it.. Then only thing i noticed i had in common was a netgear dg834g for the router. I have read that hotifx changes a lot of tcp/ip settings. it also seems to stop tools fixing the settings. Didnt matter what client i tried. Sometimes it would work sometimes it wouldnt.. on many different pcs.. It also effected dc client software.. all connected to same router
One pc is hard wired to router other is wireless..
Remember the simple solution is remove hotfix 893066
and u cant fix it with drtcp or other tcp utilities
http://support.microsoft.com/?kbid=893066
It affected both my XP laptop and win 2K pc
Thankyou for the solution.. And I hope this helps anyone else having uploads hang. but everything else is ok.