We are using FreeIPA for Linux accounts and a Windows DC for Windows accounts. Users were able to access their Linux file systems from Windows using their windows user name and password. After upgrading samba from samba-4.10.16-7.el7_9.x86_64 to samba-4.10.16-18.el7_9.x86_64 users cannot authenticate and I get the following error message: 1.2.3.4.log: ../../source3/auth/auth_util.c:1889(check_account) check_account: Failed to convert SID S-1-5-21-xxxxxxx-xxxxxxx-xxxxxxx-1158 to a UID (dom_user[DOMAIN\username]) Winbind is still running My smb.conf: [global] netbios name = HOSTNAME security = ADS workgroup = DOMAIN realm = DOMAIN.FULL.NAME socket options = TCP_NODELAY IPTOS_LOWDELAY SO_RCVBUF=131072 SO_SNDBUF=131072 use sendfile = true dns proxy = no log file = /var/log/samba/%m.log max log size = 50 log level = 1 client signing = required server signing = auto [Tmpdisk] comment = TMP-Disk public = yes path = /tmp browsable = Yes read only = No Nothing else updated or changed. What do I miss? This setup was working for years.. Thank you in advance! Gerhard Schneider -- Gerhard Schneider Institute of Lightweight Design and e-Mail: gs at ilsb.tuwien.ac.at Structural Biomechanics (E317) Tel.: +43 1 58801 31716 TU Wien / Vienna / Austria Fax: +43 1 58801 31799 A-1060 Wien, Gumpendorfer Straße 7 http://www.ilsb.tuwien.ac.at/~gs/