We are doing a total domain migration after experiencing numerous, never-before-seen problems with our AD (problems that Microsoft told us we were out of luck on). As part of this process we need to move all mailboxes to the new domain. To our understanding this is best done with either the Exchange Migration Tool or ExMerge. We have had little success with either. Does anyone know the best order in which to use ADMT 3.2, Exchange Migration Tool and/or Exmerge to move mailboxes between forests and servers?
Here is some more information regarding our network:
AD is fully 2008 R2
Everything is running (in relation to this problem) on VMware ESX/ESXi
Domain name of old domain is 'companynameglobal.com'
Domain name of the new domain is 'companyname.lcl'
The DNS suffix we use for all our email addresses is 'companyname-global.com' (Notice the hyphen)
Notice that these are not in the same forest at all
The 2 forests are setup with a 2-way external non-transitive trust
We've followed ADMT steps and haven't had any problems that we need help with in the ADMT process
DNS conditional forwarders have been setup between domains and all DNS routing is working just fine
The Exchange servers are not configured to route mail between them at all
We need any solution (that doesn't include buying Quest Software's $$$ solution) that will allow us to migrate as transparently as possible across these domains/forests. As we have only a small staff overseeing 100+ users (many of them remote) we won't be able to tolerate a large scale (big downtime) transition.
All comments welcome!