Having a problem with upload

[TEMPTii]

Whenever I try to upload something to the internet I get an error. I tried uploading to different hosts like rapidshare, filefront, mediafire, and megaupload and I still got an error. Filefront told me it was an IO error but I'm not sure which one. Any suggestions on how to fix this?

[Snaver]

Try a different browser?

[Maniac]

Have you recently had a virus ?
You are using firefox right? i assume the proxy connection settings are correct, but go check the same settings for internet explorer, i bet its set to detect a proxy.