Our receive connector on Exchange 2010 is accepting dodgy emails which pretend to be sent from our own server which means if the dodgy email slips though - it will be seen as an internal one.
My domain : mygroup.co.uk
Sender's email address in dodgy email : firstname.lastname@example.org
What should I untick on receive connector to stop this from happening ?
Juts now I have ticked : Anon users, Exchange servers, legacy Exchange servers.