Dear Lister; I have 2 machines that used mail server with windows NT (different domain) and the mail application is exchange 5.5 and i use site connector and directory replication to connect each other. and this is running fine... and i have plan to migrate from exchange 5.5 to exchange 2003. but i want to know about the connector instead of site connector in exchange 5.5 to connect with exchange 2003. 1. how can i connect between exchange5.5 to exchange 2003 ? 2. how can i connect between exchange 2003 to exchange 2002 ? any suggest would be appreciated... Best Regards; Amos D. Galiardo