Email rejected

[#1]

I've got an issue on one of my domain email address's.
Someone whose been sending me emails of various sizes with and without attachments regularly had an email rejected yesterday with the following message -
avasin14.plus.net rejected your message to the following email addresses:
Your message couldn't be delivered because the recipient's email system reported the following error: '552 Spam Message Rejected '. It's possible it's a temporary issue with their email system. Try to resend the message. If the problem continues, contact the recipient by some other means (by phone for example) and ask them to tell their email admin about the problem. Be sure to give them the error above, as it will better help them diagnose the problem.
For Email Administrators
This error is being returned by the recipient's email system but it doesn't include a valid, specific, enhanced SMTP status code, making it difficult to assess exactly what the problem is. Please carefully examine the error reported by the recipient's email system to help diagnose and troubleshoot the problem. Only the recipient's email admin will be able to fix this.
I've had this issue once before on this particular email address for a different sender. In both instances they've sent emails to a different version of my domain ie info@ rather than enquiries@ with no issues.

[#2]

I've had similar problems over the past couple of weeks - have a support question open in the PlusNet Help Assistant but no resolution yet.

[#3]

Quote from: rockposer

I've got an issue on one of my domain email address's. Someone whose been sending me emails of various sizes with and without attachments regularly had an email rejected yesterday with the following message

If you can message me the address their sending from, the address they're sending to and a copy of the email contents (including any signatures etc.) then I'll take a look.

Quote from: bobhogg

I've had similar problems over the past couple of weeks - have a support question open in the PlusNet Help Assistant but no resolution yet.

Ditto, forward me the same information (some of it's missing from your support ticket) and I'll see if I can fix it.