Just install samba server:

apt-get install samba

edit the config:

nano /etc/samba/smb.conf

set security to “share”

security = share

and guest account to nobody

guest account = nobody

then you just need to create your share like this:

[guest share]
comment = a guest share
path = /path/to/files
browseable = yes
read only = yes
guest ok = yes

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2. Join Debian Lenny to Active Directory using Samba