solange trombini \(msft\)

So, right now you already have Exchange 5.5 and Exchange 2000 in your
environment, but they are two different Organizations, right?

Well, if these two servers are in a domain or maybe in two different domains
that are part of the same forest, you will have few options:

a) You will not be able to upgrade the 5.5 to Exchange 2000, unless you
remove your Exchange 2000 and reinstall it joining the Exch5.5 Organization;
or

b) If removing and reinstalling is not an option, instead of upgrading the
Exch5.5 to Exch2000, you may decide to extract the data from the mailboxes
of these users to PST using the ExMerge took, then uninstall Exchange 5.5 of
the current server and install Exchange 2000 on this server joining the
Exch2000 Organization.Then use the Exmerge to import the data to the new
server; or

c) Migrate the users from the Exchange 5.5 Org to the Exchange 2000 Org
using the migration tool that comes with Exchange 2000 SP3.

Remember: one Exchange 2000 Organization per Forest.

Please let me know if it helps.

--
Solange Trombini
Microsoft Support Professional

This posting is provided "AS IS" with no warranties, and confers no rights.