Upload Test Error

I just purchased a new desktop computer yesterday with Windows 7 installed. I installed Avast Free Edition and Zone Alarm as soon as it was setup. With both of my protection programs running at the same time and visiting Speedtest.net or my Roadrunner broadband test sites, the download test runs fine, but when it starts the upload test starts, I get a message saying “Upload test error. Upload test returned an error while trying to read the upload file”. Now…if I disable Avast, BOTH tests work fine. I then re-enable Avast and have the same problem. Then I shut down Zone Alarm, and again…BOTH tests run fine until each program is enabled together again.

I have both of these programs installed on 3 other XP computers and have not had any problem with those. It’s just this new computer. Everything is set the exact same way on all of them.

What could be causing this? What can I do to correct the problem? Any help would be greatly appreciated.