Hi, So, I have 2 different domains S and M (under windows 2000), each one protected by a firewall (ISA). My users have one account on the both domain with same login and password. My S domain owns my exchange server, and all my users work on the M domain that owns file servers... Now my problems are: 1) Under Outlook, I can't reach internet POP3 servers to check if I have mails in if I haven't allowed all the IP traffic. I miss to open one of the ports I need (I think) but I don't know which one and I don't know if it is under "Protocol Rules" or "IP Packet Filter". So... if you can help me... 2) I have the same problem with ICQ... 3) Here, I mail to the list via OWA because my Outlook can't send anything! It can receive, but no way to send, all is moved to "Outbox" and never sent. If you have information about it, even an URL, please answer me. Thanks Thierry