I've been puzzled over this for almost a month; when running the ADFS configuration wizard I was presented with a duplicate SPN issue and informed I'd have to manually set it later. When attempting to manually set it from the command line, I'm presented with an error that there's a duplicate, however I can't really understand what's presented.
Included below is what CMD presents to me, I'd be really grateful of any help anyone can give. The issue is causing me grief with Dynamics CRM as it's authenticated via Kerberos using ADFS, I'm new to Dynamics, so forgive the noobishness. (- :
HamualC:\Users\Administrator>setspn -a host/adfs.mydomain.com ADFS
Checking domain DC=mydomain,DC=com
Duplicate SPN found, aborting operation!