At 4PM -0400 on 18/10/12 you (Steven Kiehl) wrote: > > I'm using dovecot 1.2.9 in a postfix/dovecot setup and I'm having issues > with receiving spam where the "from" header contains an address like > account...@mydomain.com. Is there some way I can filter out these emails > coming from outside our network with an account associated with our network > which doesn't exist? Do I just need to configure some custom process to > evaluate these addresses, or is there some way either in dovecot or > spamassassin to do this?
You want to do this in Postfix, with either the smtpd_reject_unlisted_sender parameter or the reject_unlisted_sender policy in smtpd_sender_restrictions. You will need to make sure Postfix has access to the list of valid mailboxes at your domain, which it should have already for recipient checking. Ben
