Enable Users To Block Senders In the Defender Portal

TempStar 50 Reputation points
2024-04-24T17:02:27.45+00:00

Recently staff have lost the ability to block senders via the ******@messaging.microsoft.com email that is sent to their inboxes.

User's image This option is also greyed out in the defender portal for them as well.

User's image We have a policy in place that is supposed to allow this action so it is not clear as to why this is not available.

User's image

I did find an article stating that MS is taking this away by default however creating a policy should allow this i would think. I am looking for feedback on anything i may have missed.

Thank you in advance.

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  1. Anonymous
    2024-04-25T11:09:55.08+00:00

    Hi,

    I checked the official Microsoft documentation and it is recommended to create a new quarantine policy if the NotificationsEnable Policy is not in effect. You can refer to this URL for the exact steps:

    Quarantine policies - Microsoft Defender for Office 365 | Microsoft Learn.

    1 person found this answer helpful.
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  2. Alberto-6036 10 Reputation points
    2024-08-13T12:09:49.0133333+00:00

    I am experiencing the same issue. The 'Block Sender' and 'Deny' options are greyed out, and nothing changed despite following the steps in the 'Manage quarantined messages and files as an admin' document. I have granted global administration privileges and security administrator privileges, but it still didn’t resolve the issue. How is it possible that even an admin cannot block senders from quarantine?

    1 person found this answer helpful.
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  3. Evandro Amaro 0 Reputation points
    2024-05-27T14:17:40.27+00:00

    Hello everyone. I too am having the same exact issue.

    User's image

    User's image

    The notification policy allows users to Block sender

    I have disabled this policy and re-enabled it 2 weeks ago. I had to to other stuff in the meantime. While getting back to this topic I checked again and still the same. The screenshot above is from today.


  4. TempStar 50 Reputation points
    2024-07-04T13:31:38.73+00:00

    Check to see if you have one of the preset security policies turned on. I had the standard protection policy turned on and once it was turned off, the ability to block senders returned.

    User's image

    Ensure you have good anti-phishing, anti-spam and quarantine rules created before turning this off.

    Hope this helps

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  5. Coridyn Fitzgerald-Hood 0 Reputation points
    2024-11-12T05:19:08.7+00:00

    Going by the answer from Andy David on this question "Block sender and Deny Options are Greyed Out" it's only possible to block senders for your own mailbox.

    That is, it's not possible to use the "Block sender" button to block senders for another user's mailbox or for a shared mailbox.

    I was able to confirm that when viewing all emails in quarantine the "Block sender" button was greyed out and disabled. But when I filtered the "Recipient" list to "Only me" and selected a message for my mailbox, the "Block sender" button was enabled and clickable.

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