I expect this question is asked time after time, but here goes.
We currently have Exchange 5.0 Server, single site, single server. We wish
to set up a new Exchange 5.5 Server on a new NT Domain and migrate our
mailboxes to it, then take down the Exchange 5.0 server.
I've looked in Technet and I reckon the way to go is:
1. Upgrade current 5.0 server to 5.5 SP 2.
2. Install new server with 5.5 SP 2.
3. Migrate mailboxes using the tool supplied with SP 2.
If this is just too much hassle we could simply forget changing domain name,
add the new server to the existing organisation and migrate the mailboxes.
Thanks in advance