Today I got an Undelivered Mail Returned to Sender message when I used Mail on my iMac.
The message was sent to one person and copied to another.
The copy got through okay but the other person's message failed.
The error was:
#5.7.1 unauthorised mail is prohibited (in reply to DATA command).
What is wrong and how do I fix things?
It most likely has nothing to do with your Mail app, but rather either your internet service provider who is facilitating your ability to send emails and/or the ISP of your recipient. All ISPs servers block some IP addresses for various reasons.
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Hi Shanghai David,
We appreciate you reaching out to us about Mail. Rest assured that we'll do our best to assist you or get you pointed in the right direction.
We understand that you are experiencing issues sending a message to a contact. The article below may help.
If you can’t send or receive messages on your Mac
Also, we’d like to gather additional details that may help us be in a better position to assist you.
Is the issue isolated to a certain contact? If yes, have you had the chance to check if you can send a message to your contact using a different email account?
These details can help us in isolating the issue
Please keep us posted.
Take care!
Thanks. Emails now seem to be getting through (same address, same ISP).
Originally, I cc'd my wife, also on on Apple mail with a mac.com email address, and the copy to her got through okay but the original to my friend (who is on @westnet.com.au) failed (but today got through). Not sure.... Anyway, things now seem to be working....
Undelivered Mail Returned to Sender
