Software Update can't check for updates because of a network problem.

Having similar issues.

Upgraded to Snow Leopard on launch last week - everything was fine until yesterday.

Last night started to get strange network issues, not being able to update iTunes, OSX etc. Some of my applications, such as DropBox also are unable to connect. Safari was slow but still able to connect.

Tried deleting the preferences and reconfiguring the network to no avail.

The odd thing is why did it start last night 09 September 2009, I hadn't actively made any changes since installing Snow Leopard...

Very strange, and annoying. Let's hope we can ID a cause and generate a resolution...

Have exactly the same issue. Same console message etc. Well, at least I know for sure others are having the same issues. Thanks for the thread at least.

I've got the exact same problem, iTunes 9 came down no problem but if I click update I get that message... hmmmm

Looks like the update server had gone offline. Mine is working again.

How's anyone else?

Had exactly the same problem. Airport Utility did not show any configuration to reset or remove. Installing manually Airport Client update (file - 10.5.8AirPortUpdate1.0.dmg) did a trick.
Good luck to all of you too! 🙂
M

Solved it! I had the same issue and just fixed my problem by resetting my proxy settings for my connections.

Navigate to Apple Menu > System Preferences > Network

In the left window pane you should see your current connections (AirPort, Ethernet, Firewire, etc.)

Select whatever connection you are experiencing the problem with and hit the minus symbol at the bottom of the pane (thus deleting the connection)

Hit apply.

Click the "Plus" button and re-add the connection(s) you just deleted.

Hit apply.

DONE!

thanks man it seems my software update working again!