Migrating SharePoint Users from one domain to an other

For question about migrating users between domains, even though you have used the Active Directory Migration Tool to migrate your users from Domain A to Domain B, and have chosen to preserve SID history, users in Domain B are logging in to MOSS 2007 as though they are new users. In order to migrate the users over you will need to use the STSadm command listed below.

stsadm -o migrateuser -oldlogin DOMAIN \ user -newlogin DOMAIN \ user [-ignoresidhistory]

This command must be run on a per user basis. As this is the case, it may be advantageous to write a custom application that will pull users programmatically and update them all at once. Another option for this would be to use Powershell to do the same. More information about the stsadm command listed above can be found in the KB Articles linked below.

After you migrate a user from a different Active Directory domain, the user can no longer access Windows SharePoint Services
http://support.microsoft.com/default.aspx?scid=kb;EN-US;896593

A user can no longer access SharePoint Portal Server 2003 after you migrate that user from one Active Directory domain to another Active Directory domain
http://support.microsoft.com/default.aspx?scid=kb;EN-US;896161

The commands above work for users, but not for groups. Domain Groups will have to be manually added back to SharePoint and re-assigned the appropriate rights.

For more information about move and migrate servers and server farms (Office SharePoint Server 2007), please refer to the following article:
Move and migrate servers and server farms (Office SharePoint Server 2007)
http://technet2.microsoft.com/Office/en-us/library/42511e01-ecdd-4dc5-b06f-35aaada8a5d81033.mspx?mfr=true

Moving SharePoint to a new active directory domain
http://justgeeks.blogspot.com/2007/09/moving-sharepoint-to-new-active.html

move SharePoint to a new domain
http://sharepointapplied.com/2009/02/04/move-sharepoint-to-a-new-domain/