how to block domains

Question

How can I block emails from a specific domain?

Answer 1

Dear nabtech (nabtech),

Thank you for posting to Microsoft Community. We are happy to assist you.

We are looking into your situation, we will update the thread shortly.

Appreciate your patience and understanding and thank you for your time and cooperation.

Sincerely,

Simbarashe | Microsoft Community Moderator

Answer 2

Dear nabtech (nabtech),

Good day!

Thank you for posting to Microsoft Community. We are glad to assist.

As per your mentioned description about "how to block domains". Kindly check with below step to block email from a specific domain.

• Kindly go to Microsoft 365 admin center (Enter your username and Password)-->Show all-->choose Security under Admin centers or go to Microsoft 365 defender direct by visiting https://security.microsoft.com/
• Go to Policies & rules > Threat Policies > Rules section > Tenant Allow/Block Lists
• On the Domains & addresses tab, click  Block.
• In the Block domains & addresses flyout that appears, configure the following settings:
  • Domains & addresses: Enter the specific domain you want to block.
  • Remove block entry after: The default value is 30 days, but you can select from the following values:
    • 1 day
    • 7 days
    • 30 days
    • Never expire
    • Specific date: The maximum value is 90 days from today.
  • Optional note: Enter descriptive text for why you're blocking the email addresses or domains.
• When you're finished, click Add.

Important Note:

• If you are not Admin, kindly contact your organization Admin to perform above steps.
• Users in the organization can't send email to these blocked domains and addresses. They'll receive the following non-delivery report (also known as an NDR or bounce message): 550 5.7.703 Your message can't be delivered because one or more recipients are blocked by your organization's tenant recipient block policy. The entire message is blocked for all recipients of the message, even if only one recipient email address or domain is defined in a block entry. For extra reference kindly refer to Allow or block email using the Tenant Allow/Block List - Office 365 | Microsoft Learn

Please feel free to let me know if there are any updates or if I've got you wrong. I will keep assisting you based on the information you provide. We sincerely appreciate your patience and cooperation. Thanks for your precious time. Have a nice day!

Best regards,

Inema | Microsoft Community Moderator

Answer 3

Hello all. I am being bombarded with spam email. It seems that domains that end with .xz and .one are mostly individual domains. I get more than 50 daily between the two. The vast majority of these are from adult content. 😞🤬

I tried adding .xz and .one as typed in this sentence along with several others such as .ra and this doesn’t work.

Does anyone have a suggestion that would help eliminate receiving these emails from entering my outlook.com Account? I’m at the point of considering creating a new account. This is a tremendous task which I have done before but am trying to avoid this. Everything is tied to this outlook.com account. Finances, friends and relatives, job searching etc

Answer 4

Here's the Rule I use in the Exchange Admin Center.

I don't actually delete the items, I send them to the end user's Junk Email folder. I also receive a Report so I can monitor how it's doing. I would recommend the same to test before you take the drastic action of blocking a whole TLD.