We have MS Exchange 2003 and I would like to ask if our SMTP is secure against spam with the below settings of SMTP.
as I quite often find in the Exchange system manager queue, that other servers are trying to send Spam emails using our server - the emails are waiting in the queue for next connection retry - how can I avoid it? I would like these emails to be rejected by our server immediately...
our SMTP settings is:
Anonymous access - CHECKED
Basic authentication (password is send in clear text) - CHECKED
Integrated Windows Authentication - CHECKED
All except the list below - CHECKED
(we have the list empty)
Only the list below - CHECKED
(the list is empty)
Allow all computer which successfully authenticate to relay, regardless of the list above - CHECKED