another zone alarm query

Hi all, i hope you'll be able to help me out here.
i have zone alarm pro version 5.0.590.015 installed on my machine and all is good and well. i recently set up a home wireless network at a friend's and again all is well, at least with my machine.
i installed the same version on my friend's machine and she cannot access the network unless zone alarm is shut off. both machines have an almost identical setup including xp service pack2.
when i view the network in 'firewall/network/zones' it is listed there (same as mine) with 'internet' as the trusted zone (same as mine). yet my machine can access the internet and hers cannot. all other firewall settings have been set up identical as mine. i am at a complete loss and as i am so fond of zone alarm (it's been flawless on my machine so far) i am loathe to remove it and use another.
any ideas that i may not be seeing for the trees?
thanks good people
pixleshifter