I've been getting "Tempoary Failure" and then "Permanent Failure" for certain emails to the 2 same recipents. Only some of the emails to these recipients are getting the fails. It is a business address. They checked on their end and they can't find a problem. They check and told me they received 23 emails sent to their servers and none were rejected. I counted on my end and found 28 sent. Any help would be appreciated.
If the messages didn't go into your recipient's Spam folder, I would call Comcast security and see fi there is any blocking issue for that other domain.
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