[Samba] possible reason for 'ERRnoaccess (Access denied.)' with 'securty = user' and correct username, password ?

[Yakov Lerner]

If 'security' is 'user' in smb.conf, and I provide correct username
and password in 'mount -t smbfs -o username=USER,password=PASSWORD ...
' and mount fails with 'ERRnoaccess (Access denied.)', then what can
it be ?

I use nonstandard port ' option port=123 on the smbclient side, and -p
123 on the samba sevrer side, on the smbd command line). Can be this
troublesome ?

Thanks
Yakov