enabling anti spoofing spam from own ms-exchange domain

[esetuser22222 0]

Hello, 

I would like to enable the "ANTI CEO FRAUD"  Spoofing Function in latest ESET Mail Security Version.

prerequisites:
mx DNS s pointed directly to the MS Exchange  = OK
no other one is sending emails from our own mail-domain example.com  (like homepage contact-form)

In Case I forgot something, thx for info.