Users report problems searching in iTunes 7.1.1
Jason O'Grady of ZDNet posts that thousands of Windows users are having problems with iTunes 7.1.1, which they believe will not allow them to properly search the iTunes store. Their search goes into an endless wait, and then they get a message that their iTunes request could not be completed.
It seems to me that Apple's response, namely that the "network connection timed-out" error is an Internet problem not a software problem, sounds reasonable. When iTunes connects to the store, it's sending out a request for what is essentially a webpage and this request can hang for any number of network reasons--including those on the Apple end.
O'Grady suggests that users may have to uninstall iTunes 7.1.1 and re-install iTunes 7.0, but I'm not sure that is necessary. The original Apple discussion list thread is here.
