I even tried installing the new iTunes (version 8), since their help site said it was version 7 that was having problems. Didn't help at all.
The problem only just started maybe a week or two ago. Before then, I had no problem making purchases. The only thing I can think of that's changed since then is that my school network has switched over to a client program called Odyssey Client. Some of the network settings I'm sure are being controlled by an outside administrator, but I should be able to enable iTunes on my own computer, right?
Help! I'm desperate to buy more music!
Well, nevermind. I feel stupid now...turns out it was a problem with the proxy we use. Trust my school to do something like that! Future reference for anyone experiencing similar issues (I know my classmates are), check your proxy settings. Thanks for trying to help, though!
Edited by greschel, 15 September 2008 - 11:06 PM.