Failed Windows Update = Faulty Domain Controller Windows 2012 =Restart loop = Dead Exchange 2013

To be continued



Get-ExchangeServer –Identity <server_name> -Status | FL

set-exchangeserver -identity servername -staticexcludeddomaincontrollers: oldservername

How to change domain controller name that exchange sees

  https://technet.microsoft.com/en-us/library/jj592690.aspx

 
nltest /dsgetsite
DSGetSiteName failed: Status = 1919 0x77f ERROR_NO_SITENAME
nltest /dsgetdc: FQDN of your domain  


From regedit; drill down the following:
HKLM\System\CurrentControlSet\Services\Netlogon\Parameters
Once you click Parameters, add a string word called “SiteName”
as written here https://messagingschool.wordpress.com/2014/04/18/dsgetsitename-failed-status-1919-0x77f-installing-exchange-2013-sp1/

 
Get-ClientAccessServer | Test-MRSHealth



-StaticExcludedDomainControllers
https://technet.microsoft.com/en-us/library/dd298163%28v=exchg.150%29.aspx

--

import-module addsdeployment
uninstall-ADDSDomainController -ForceRemoval:$true -Force:$true
https://technet.microsoft.com/en-us/library/jj574104.aspx
http://sysadminconcombre.blogspot.hu/2014/03/scenario-my-test-lab-consists-of-3.html
http://chinnychukwudozie.com/2014/01/27/using-ntdsutil-metada-cleanup-to-remove-a-failedoffline-domain-controller-object/

Finally, check if your DC is really gone:
Detailed list:
Get-ADComputer -LDAPFilter "(&(objectCategory=computer)(userAccountControl:1.2.840.113556.1.4.803:=8192))"
another method to the same detailed list:
Get-ADDomainController -Filter * | Select-Object name
or a simple list:
Get-ADGroupMember 'Domain Controllers'
(note: 'Domain Controllers' string is localized into your language)