I am running windows 2000. I do not have the cd. It is a generic dell that i have had for several years. I am running zone alarm and avast anti virus on it. Up until last weekend I had no problems. Now I can not upload any files, no matter what the type or size.Turn off Zone Alarm and try...Okay I tried it and it didn't work.What browser ?
What are you uploading?
And where ?

You haven't provided much info here......and where are you uploading to? Or maybe, you're talking about downloading?I don't THINK he's been to DEFCON... Browser: Mozilla Firefox version 2.0.0.13 (exstentions noscript, adblock, FORECAST fox)
File Types: Any files. Word Documents, mp3s, avi, jpeg, bmps. Any and all files I try to upload.
Where: Gmail, Deviant Art, a server run by a friend, three different forums. And anywhere else I try.

I have tried disabling all the extensions I have for Firefox but that didn't work either. I have ALSO tried using the latest version of IE but I still couldn't upload any files.
I can download files no problem.
It's more clear now.
When you're trying to upload, what happens? Any error messages?
Do you use router?
What firewall do you use? Did you try to disable it momentarily?
Can you upload in Safe Mode with Networking?I only get an error message when I try to attach a file with gmail. It says there has been an error with the server and the email cannot be sent at this time. Anywhere else after I try to upload it simply stops. The computer isn't FROZEN but it will not finish the upload.
I do not use a router and my firewall is Zonealarm. I have tried disabling it but even with it turned off I can't upload. I tried it in safe mode after I read your suggestion and it still wouldn't let me upload.Hmmm...pretty puzzling...
Try to create new profile.Are you aware gmail will block certain extensions for uploads ? ?