When attempting to access a resource in Active Directory via Kerberos authentication, authentication may not work. The following may appear in the logs when this happens: DirectoryService[26]: GSSAPI Error: Unspecified GSS failure.  Minor code may provide more information (Requested effective lifetime is negative or too short).

Here is the original post:
Mac OS X v10.5: "GSSAPI Error: Unspecified GSS failure" when accessing Active Directory resources that use Kerberos

Similar Posts:

• Enabling iCal server access for users of Active Directory or third-party LDAP servers
• Mac OS X Server v10.5, 10.6: Enabling Directory Service debug logging
• Final Cut Server 1.5: Active Directory bound Windows clients require a custom Kerberos configuration file for successful authentication
• Mac OS X Server 10.5, 10.6: Enabling wiki access for Active Directory or third-party LDAP server users
• Mac OS X Server v10.6: Configuring service principals in Active Directory when using a disjoint namespace