Windows XP and ICQ

I have a 2 computers linked to each other with a cross cable.
Windows XP is installed on both computers.
I installed a Firewall and VirusScanner (both Norton) on the computer with direct access to Internet.
I have a Network Bridge. I can access files and folders of each computer on the other computer. I can access mail on both computer. I can access Internet/use ICQ via both computers.
But I can't send files or start a chat via ICQ on any computer.
I already changed the login to login.icq.com and I use port 5190.
'Allow peer to peer connection with users listed on your Contact list' is checked. I also tried to use a file/start a chat after I disabled my Firewall. I (un)checked 'Using Firewall' in the Connection settings.
'Use server proxy settings' is also checked.
But even then, I still get the same message : "You cannot establish Peer to Peer connection with the other user. Please check your ICQ PeertoPeer and firewall settings and try again. If the difficulties continue, the problem may be wit the other user's ICQ Peer to Peer or firewall settings. "
The other ICQ-user confirmed me he can send files/chat with other persons but not with me.
Please ... what do you I have to change ? Where does it go wrong ? I don't have a clue !
Thanks for help and maybe solution.

 

Have you set your computers up with static or dynamic ip's? I have the same thing and fixed it by doing static ip's in my router..
This may not help you, but I thought I would try...

 

I have static IP's on my computer (network card) with direct access on Internet.
I can't use static IP's on my other computer. I tried, but I can't access Internet, email, folders, files, ... anymore.
Thanks anyway ...