Setting Up a Backup Domain Controller Stated Incorrectly (126640)

This article was previously published under Q126640

Page 38 of the "Windows NT Server Concepts and Planning Guide" incorrectly states:

   (However, if you have an existing backup domain controller in a
   different domain, you can move it from that domain to another.)
		

This is incorrect. Windows NT identifies each domain by it's security identifier (SID), a unique number assigned to the domain. If Windows NT Server is moved from one domain to another, the new domain name and the original SID will not match. There is no way to replace the original SID without reinstalling Windows NT Server.

Page 23 of the "Windows NT Server Installation Guide" correctly states the procedure of joining different domains:

   After Setup is finished, the only way a Windows NT Server computer
   can join a different domain is if you reinstall Windows NT Server.