How to Verify which Service Principal Names (SPN) are Registered with Active Directory for a Computer
To check the SPNs that are registered for a specific computer using that computer, you can run the following commands from a command prompt:
setspn -L hostname - Substitute the actual hostname for the computer for hostname(to see the hostname, type hostname as a command prompt). For example, if you typed hostname at the command prompt and the computer reported the name ContosoDC1, you could then type setspn -L contosoDC1 to see what SPNs are registered for that hostname.
setspn -L localhost - This command will check registrations for the account localhost, which is a name indicative of the local computer.