KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN

[Thomas Schweizer]

Markus Zeilinger wrote:

> I use Outlook 2003 to connect to an Exchange 2000 Server in a Windows
> 2000 Active Directory environment. As set in the options Outlook uses,
> or even tries to use, Kerberos to authenticate against the Exchange
> Server. When I sniff the network traffice I see the following packets:
> 
> 1. A packet KRB5: TGS-REQ
> 2. A packet KRB5: KRB Error: KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN

This means: Server not found in Kerberos database. There are no 
Exchange-related service principals available, which is no surprise 
since Exchange 2000 does not support Kerberos authentication; so Outlook 
falls back to NTLMSSP. BTW: Exchange 2003 supports Kerberos 
authentication (not including the POP and IMAP connector).

Cheers,
Tom