How to find out if your Mail server is an Open Relay

As more and more small businesses have started to use their own mail servers I thought it would make sense to limit the impact spammers can have.

Basically if your mail server is an open relay spammers can use your mail server to distribute thousands of junk mails.

Not only does this contribute to other users problems with junk mail it also impacts the realibility of your mail server and ultimately could cause your mail server to be blacklisted.


Best practice to make sure you are not an open relay use one of the free open relay testing sites like this one http://www.ordb.org/submit/