After you add a user and a password, you should probably test your server. To start the server, you need to run nmbd and smbd with the following arguments, where smb_config_file is the full path of your smb.conf file:
nmbd -D -s smb_config_file smbd -D -s smb_config_file
The nmbd daemon is a NetBIOS name server, and smbd does the actual work of handling share requests. The -D option specifies daemon mode. If you alter the smb.conf file while smbd is running, notify the daemon of the changes with a HUP signal.