I am currently in the process of migrating our e-mail system to exch2K, the problem I have is we wish to run both exchange 5.5 and E2K servers at the same time, the idea being that we move a few users from the exhange 5.5 server over to the 2K server at a time, I can get the user accounts to sync using the ADC but I can't then get the 5.5 server to send mail to the 2k server when it receives a message for a recipient on the 2k server (all mail comes in to the 5.5 server) At present I have this set up in a test environment. Any help, recomended reading or a kick in the right direction will be greatly appreciated.