We have required "authentication" when sending emails, and make sure no one in my server sending spam. But today, I received many returned emails, for "[email protected]", "[email protected]", "[email protected]"... you can see the address before @mydomain.com is randomly.
How can I prevent this kind of spamming? I have DA 1.27.5 with exim 4.6
How can I prevent this kind of spamming? I have DA 1.27.5 with exim 4.6