So you have gone through part 1 and now get an error saying the directory service is busy!
Is SQL Express or SQL installed? If so, from an elevated command prompt type:
setspn -L computername
Note any registered SPN in the format of
MSSQLSvc/[Computer Name]:[Instance Name]
Delete each of the SPN’s noted above.
setspn –d [SPN Name] [ComputerName]
Important: You must use the full SPN name as identified via the setspn –L command. These will be in the format of MSSQLSvc/Computer.domain.tld:instance