I have used a MS365 hosted email account (External Service SMTP) to send emails successfully for about 18 months. Queue process set to 120 emails sent every 15 minutes. No issues whatsoever. Authenticated with username and password, etc.
Then, a recent mailout failed, with Microsoft blocking the email account. I unblocked the email account. Then changed the queue process to 30 emails every 15 minutes with a wait of 15 seconds between each mail. Overly cautious but thought it might fix. Failed again. Then I received firstly 'medium' then 'high severity alerts' from Microsoft thinking my email account had been hacked citing 'suspicious email sending patterns'. I attempted to mark the warnings as false.
I contacted Microsoft and they told me that I should not be using their service for 'bulk' emails. Sending a few hundred emails is hardly 'bulk' for the largest IT company on earth!!
I then explained that their website (and a previous Microsoft employee) had told me to set sending in the way I have it set up. Their own website states this is permissable and possible within the limits I have set.
Now, they are thinking about it, and due to get back to me. Meanwhile, I can't use Acymailing the way I have been.
Anyone else having the same problem using a Microsoft 365 email account to send their emails?
Could something to do with Acymailing be flagging the send process as spam?
