We have had some issues with clients contact forms using an email with the same domain.
If our clients domain was "abc.com", I would add their "To" and "From" as firstname.lastname@example.org or email@example.com and save it. Once you go to their site to send them an email it would not work, and error would come up. If you went back and changed the emails to a generic email, gmail, yahoo or bell.net it would work.
Client really wants to use their domain emails.
How do we fix this?