Unable to access Software Update/iTunes Store

[a.b.olsen]

I have used an iBook G4 for a year and a half I only use wireless Internet connections. I recently started getting error messages when I tried to perform a Software Update.
The error reads:
"Software Update can't connect to the update server. Make sure you're connected to the Internet, then try again.
Software Update can't check for updates because of a network problem."

Perhaps at the same time (I hadn't paid too much attention at first) I found that I was unable to connect to the iTunes Store.
This error message read:
"iTunes could not connect to the iTunes Store. The network connection was refused.
Make sure your network settings are correct and your network connection is active, then try again."

A google search shows that the second error message is common among PC users who think apple is conspiring to keep them out of the iTunes store with iTunes v7.1.1.

I don't know about network settings but I don't make a point of ever fiddling with them. I assume both of these problems are symptoms of the same network mess-up. Can anyone steer me clear?

[a.b.olsen]

I tried a combo update, but it didn't help at all. Still exactly the same problems.

[JeffCGD]

Sounds like the required ports are blocked by a firewall somewhere in your network, so that Software update and iTunes are not able to communicate with the sites (though I thought that iTunes would be over http.

[pedz]

I have this issue too. I'm 99% sure that I do not have anything blocked.

I'm running 10.4 server. This happened when Leopard came out. I assume Apple just abandoned 10.4.