Vista Premium 64 web access ???

Hi All,
Just looking to see if anyone has come accross this problem with Home Premium 64 bit version.

I have been asked to collect this tomorrow to see if I can fix the problems, so thought I might do some homework beforehand...

This machine has problems with internet access. Broadband has been setup and works fine. Accessing some web pages just doesn't happen though. (Note: not my PC). Bebo, for instance doesn't work. MSN Messenger doesn't work. Limewire web site works. Other web pages works intermittently.

Security settings ?? Browser ??

Any ideas that I might try when I get it back here?

Thanks. :?

Yes it does use a hardware firewall.

Now I've got it back here, I'm using it on a connection that is shared out thru my own PC (using XP Home), via a crossover ethernet cable, and it works perfectly.
I've installed messenger, which the owner could not even download, I set up a temporary Bebo a/c, which they could not even access the Bebo homepage, and all other websites they were having problems with work perfectly !!!

Surely the router can't be that incompatible with Vista 64 ?? I always regarded routers as pretty much a pass through device that filters traffic without really being interfered with by the OS ?

Maybe I should suggest a different model ?

Thanks for the tip.
It was the Linksys Firewall causing the problem.
Updated firmware actually did resolve the issue, but the guy at Linksys advised not to use the latest firmware, but the previous incarnation instead.

Thanks.

Ty.