When my smb.conf file contains security=share, I don't have any problems, I can browse the files from another computer with ease. However, that's not terribly secure, so I change it to security=user. Now when I try to open my Samba server from another computer, a dialog box opens asking for a username and password (that's good!) but it rejects every username I try. My log files are filled up with smb_pam_auth failed. I've added and enabled the users using smbpasswd. What am I doing wrong?