This is a partial list of mu smb.conf file. Please note: you need to create an account for user ' nobody', and create a samba login as well with 'smbpasswd -a nobody', and give 'nobody' a blank password.
netbios name = samba_server
workgroup = workgroup
server string = Samba Server
# Uncomment this if you want a guest account, you must add this to /etc/passwd
# otherwise the user "nobody" is used
guest account = nobody
# Security mode. Most people will want user level security. See
# security_level.txt for details. NOTE: To get the behaviour of
# Samba-1.9.18, you'll need to use "security = share".
security = user
encrypt passwords = yes
# A publicly accessible directory, read/write to all users. Note that all files
# created in the directory by users will be owned by the default user, so
# any user with access can delete any other user's files. Obviously this
# directory must be writable by the default user. Another user could of course
# be specified, in which case all files would be owned by that user instead.
path = /usr/shared_folder
only guest = yes
writable = yes
printable = no
browseable = yes
create mask = 0777