I had an error in the event log on every SharePoint 2010 farm server:
A Kerberos Error Message was received: on logon session Client Time: Server Time: 13:1:13.0000 3/17/2011 Z Error Code: 0x7 KDC_ERR_S_PRINCIPAL_UNKNOWN Extended Error: 0xc0000035 KLIN(0) Client Realm: Client Name: Server Realm: xxxxx.NET Server Name: HTTP/xxxxx.net Target Name: HTTP/xxxxx.net@xxxxx.NET Error Text: File: 9 Line: efb Error Data is in record data.
This happens after migration of the old MOSS 2007 farm to SharePoint 2010. – On the new farm I used new accounts for the application pools.
I created SPNs on the new Application Pool accounts for the web applications.
BUT I forgot to remove the same SPNs from the old Application Pool accounts!!! – This was the (big) mistake.
ADSIEdit let me create the same SPN on different accounts.
After removing the SPNs from the old Application Pool accounts everything works fine!
use SETSPN-Tool to find the accounts:
setspn Q HTTP/xxxx.net
You’ll get a list of all accounts that have the specified SPN “HTTP/xxxxx.net”