User mailbox getting locked out

Question

David intermittently needs to send emails external from his account (d*****@domain.com) to external contacts. These external contracts include (but not limited to) hotmail.co.uk, yahoo.co.uk, gmail.com addresses. The emails are generally sent out in bulk. However, after a short period of time they are being blocked by the Exchange Online Protection (EOP) rules and his user account is being blocked/added as a restricted entity. In turn his account needs to be manually unblocked. This process is documented in at the below URL: https://learn.microsoft.com/en-gb/defender-office-365/outbound-spam-restore-restricted-users This rule is enabled by default and doesn’t look like it can be disabled. Is there a way to exclude this user account from the above rule on a temporary basis allowing these emails to be sent?

Answer 1

Hello Leo.Grégoire**,**

Good day! Thank you for reaching out to Microsoft community.

As per your description and my understanding, David's mailbox is being intermittently blocked by Exchange Online Protection (EOP) due to bulk emails sent to external contacts, including domains like Hotmail, Yahoo, and Gmail. These actions trigger EOP's outbound spam detection rules, causing his account to be flagged as a restricted entity.

As a result, his account must be manually unblocked, following the documented process. You’re seeking a way to exclude this account from these rules temporarily to allow bulk emails to be sent without being restricted.

While you can't disable the rules entirely, you might be able to adjust the EOP policies to reduce the likelihood of David's account being flagged. For example, you can use the Set-EOPProtectionPolicyRule cmdlet to create exceptions for specific conditions.

Use the Set-EOPProtectionPolicyRule cmdlet to modify rules that are associated with Exchange Online Protection (EOP) protections in preset security policies.

• Here is the reference: Set-EOPProtectionPolicyRule (ExchangePowerShell) | Microsoft Learn.

Please follow these steps and let me know the outcome. If the issue persists after completing the above, feel free to reach out, and we can further investigate the problem together.

Thanks for choosing the MS community.

Looking forward to your response and have a great day ahead!!

Sincerely

S M Nazmun Nur | Microsoft Community Moderator

Answer 2

Hello Leo.Grégoire**,**

Thank you so much for your feedback.

I hope this works.

If you need any further assistance, please don't hesitate to let us know. We're here to help.

Thank you for your time and cooperation.

Merry Christmas!

Sincerely

S M Nazmun Nur | Microsoft Community Moderator

Answer 3

Thanks for your response. Will check this after holiday

Wishing you a very merry Christmas!