Good morning everyone!
I've been trying to do an SBS migration from 2008 to 2011 but I keep getting the dreaded 'Server was not promoted to Domain Controller' error.
In the log, it lists error 54 - ExitPromoDemotFailed
followed by error 26 - ExitUnableReadDomainList
The source server is completely up to date with Exchange SP3, and all Windows updates. I ran the Migration Prep Tool, found no problems and made my answer file.
Here are some of the things I tried:
Made the administrator password extra complex (it now has a capital letter, lowercase letters, numbers and a special character.) I rebooted after changing the password
Made sure the date, time and time zone are the same on both servers
Turned off IPv6 on the 2011 server
Made sure all unused NICS are disabled on both servers
Made sure there only DNS entry in the network config of the 2008 server is its own address (the ISP's DNS was also in there and I deleted it, then cleared the cache and restarted DNS)
Seized back the schema master, infrastructure master, domain naming master, pdc master roles to the 2008 box before trying SBSSetup again. On my first attempt, they transferred to the 2011 box, but the roles stayed on the 2008 box after I seized them back even after trying the installation several more times)
Tried making the answer file with the DHCP box both checked and unchecked (it is running on the 2008 server)
I am able to ping the 2008 server from the 2011 server using the name.