Combining two Active Directory Domains

I'm assuming that the user accounts are in the new domain and not the old domain.  If this is the case, then do the following in this order:

1. For each server (except the Domain Controllers), remove it from the old domain and join it to the new domain.
2. Make sure that users can access resources on the servers after the move, such as printers and shared folders
3. For each domain controller (except the FSMO holder*), demote the domain controller and then move it to the new domain as a member server.
4. For each of the DCs that have been moved, make sure users can access resources on those servers
5. Before demoting the last domain controller that has the FSMOs for the old domain*, do this:
  a. Remove all of the trust relationships that exist between the domains
  b. Remove all instances of DNS for the old domain that may exist in the new domain
  c. Ensure that all resources, users and computers have been migrated and that everyone can access everything
6. Demote the last domain controller in the old domain.
7. Join the las domain controller in the old domain to the new domain.

* I'm assuming that all of the FSMOs are on one server.  If not, then you'll want to transfer them all to one server.  Allow an hour for AD replication/GC replication to complete

Also, if all of your users haven't been migrated yet, you'll run into problems.  Migrate them first, if you haven't already.

That's pretty much it.  Good luck!

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I would plan on everything failing, that way you take the proper precautions and back up EVERYTHING.  :)

Here's how I would handle SQL:

1. Document how SQL is set up on the existing server.  Pay special attention to the logins and what rights they have been granted.  Also, make sure you know what service account is being used (it the logon account for the SQL services)
2. Install SQL on a different server in the new domain.  Regardless of how you're currently set up, make sure there's an account in the new domain which you can use as the SQL service account.  If you don't have hardware available, then create a virtual machine.
3. Backup the SQL database on the existing server and then restore it on the destination server.
4. Test it.  Make sure that you can do everything you're supposed to.  You'll most likely have to recreate some of the logins you documented in step 1 above.
5. Assuming everything works well, then I'd do this to move the SQL server:
 - Stop the SQL services and change their startup type from Automatic to Manual
 - Copy the SQL data directory to another server somewhere on the network
 - Migrate the server the way you do the others
 - Assign the SQL services the new service account for the new domain and make sure they start
 - Test everything again

It's not as complicated as you might think.  Just make sure you back up everything - the entire Data directory - not just your specific DB and log files.

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No worries at all!  Did it work out okay?

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Ha!  No.  I hate Sharepoint.  My only experience with it has been nothing but frustration.

Good luck with that!

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