Hello-

Background:

Currently at a client that is migrating/consolidating 6 different
domains into one new domain.

One Exchange 2003 (SP2) server in its own domain.

Users logon to workstations locally - not logging onto domain.

Desired End-State:

New Domain

New Exchange 2003 Organization - same SMTP domain name.

We have chosen to migrate user accounts (w/SID history) and mailboxes
from current email domain - mainly because all users across
organization have mailboxes in email domain.

File and other security are to be recreated in new domain.

Migration is planned to be department by department.

Would like to get opinions on how to migrate one department at a time,
while maintaining GAL contact between the new and old email domain.
There is currently an SMTP connector between the old and new domains to
forward a few test accounts that have been migrated to the new Exchange
org.  In the place of mailboxes in the old Exchange org, users have
been enabled with external email accounts.  Essentially - contacts,
instead of mailbox users.  These users are seen in the GAL in the old
domain.  No problem there.

I would like to find a way to automate this process - instead of
manually inputting email contact info; I would like to have the email
information updated in the old domain as the email accounts are
migrated to the new domain.

I have considered using IIFP, but not sure if this is the appropriate
measure.

Also would like opinions on updating Outlook profiles on workstations
not attached to the domain.  In the past, I have been able to do so
using the Exchange Profile Update tool via login script or GPO.

Opinions are very much appreciated.  Thank you.