Hello, 

Thank you for reaching out to SmarterTools. My name is Zach I will be helping you with this question. 

Most likely what is happening here is that the sender is failing DKIM or SPF when this happens the trusted sender status is revoked. The reason for this is that if it fails those checks it could be someone impersonating that email. 

To get around this you could create a custom spam check at the system level that looks at the To: header for an email from that user then gives it a score of -99. 

Heres an example. 

Please let me know if you have any questions. 

Kind Regards, 

Hi, Zack.  Thanks for your post.  Two followup requests:

1) The image you posted is too dark for me to read.  Would you please post a more readable version?

2) How can I arrange to be notified by email when someone responds to one of my posts?

Thanks,

Tony

Zach:  I forgot to thank you.  Thanks.

Hey Tony, 

It's no problem. I love to help. 

Have a great day. 😃

Kind Regards, 

Hi, Zach.  I only now have had a chance to implement your advice of 2/28/22 🙄 and I think the Settings screen may have changed enough (see below) I need to ask you for new instructions.  Thanks.

Tony

Hello Tony, 

Thanks for the follow-up. This is a domain admin account in order to complete the steps above you will need to use a system admin account.

Kind Regards, 

It would be very helpful if we had the option to limit the scope of these rules per-domain... or give us the option to create these rules INSIDE the domain rather than at the global level.  We're in that situation now where one specific customer wants all emails from a particular bulk mailer (mailgun) whitelisted because much of their important listmail comes from there, but we don't want to do it for any other customer because that service also blows out a lot of spam.  So we're stuck between a rock and a hard place.