Can no longer send bul emails with a pdf attachment

Question

I am secretary of a club and until recently I have been able to send out bulk emails with a PDF attachment. When I try that now I get a postmaster message with 'Remote server returned '554 5.7.0 < #5.7.520 smtp;550 5.7.520 Message blocked because it contains content identified as spam. AS(4810)>'' message. How can I fix this please

John Nankivell

Answer 1

Hi John,

I will walk through a few steps with you. Some of these are just to help figure out what is wrong, not to fix it right away. So if nothing changes after a step, that is normal. I will keep going until we solve it.

May I know how many emails you send per day in a group?

Do you have a Microsoft 365 subscription?

Have you tried removing your signature, if any and then send?

I look forward to hearing from you to get the results of the troubleshooting.\