Hi, We have upgrade samba from 3.6.23-36 to 4.6.4, but we got "*Logon Failure Unknown user name or bad password*" error while trying to access samba form window 2003. And we use usename and password to login, not by the AD. We also test on windows2008 windows2008-R2 window7 windows10, it works. Thanks. Lifeng Ren