Hi list, I am able to successfully authenticate a Windows server AD user with PostgreSQL 9.2.3 version from linux clients but It doesn't work with Windows client. First I logon windows 7, using a Active Directory's user, then I tried to login to postgresql 9.2.3 server with psql: psql -h hostname -p 5444 psql: SSPI continuation error: The encryption type requested is not supported by the KDC. (80090342) postgresql.log : -1 log: connection received: host = 172.XXX.XXX.XXX port = 61877 -1FATAL: GSSAPI authentication failed for 'userXX' user userXX exists in our postgresql server and pg_hba.conf applied to 172.XXX.XXX.XXX subnet is: host all all 172.0.0.0/8 gss Our postgresql.conf use keytab: krb_server_keyfile = 'postgres.keytab' And I have generated keytab with this ktpass command: ktpass -out postgres.keytab -princ postgres/hostname@domain -mapUser postgres -pass XXX -crypto DES-CBC-MD5 The postgres user, exists in the Active Directory and it has a spn defined: C:\Users\Administrator>setspn -S postgres/hostname domain\postgres Checking domain DC=domain Registering ServicePrincipalNames for CN=postgres,CN=Users,DC=domain postgres/hostname Updated object If I login from a linux client to linux server, there is no problem: [root@hostnane datos]# su - userXX [userXX@hostname ~]$ klist Ticket cache: FILE:/tmp/krb5cc_503 Default principal: userXX@domain Valid starting Expires Service principal 12/11/13 08:42:04 12/11/13 18:42:09 krbtgt/domain@domain renew until 12/18/13 08:42:04 12/11/13 08:42:43 12/11/13 18:42:09 postgres/hostname@domain renew until 12/18/13 08:42:04 [userXX@u2vbddpg ~]$ psql -h 172.XX.XX.XX psql (9.2.1.3) Type "help" for help. edb=> Thanks -- Sent via pgsql-admin mailing list (pgsql-admin@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-admin