Transfer FSMO or flexible single master operations roles
July 13, 2009Raise your domain functional level
July 13, 2009run adsiedit
navigate to:
In the below example sitename and servername is the server you’re deleting.
configurationcn=configurationcn=sitescn=<sitename>cn=serverscn=<servername>
Right click on cn=ntds settings and select delete
Once this is done you can delete the server normally from active directory sites and services