How to block domains so they don't even go into Junk

Question

I got hundreds of junk emails from specific domains every week. If I block a domain, it only gets blocked from my inbox. I would like to have them be blocked in junk mail so I don't see all the spam I get. It seems spammers change the domains every few days, so if I block a sender, it invariably comes back with a different domain, but the same trash. I have also created rules, but again they only apply to inbox. Not junk. If I don't look at emails for 2 days, I have over 200 junks to scan through to be sure something I would want doesn't get lost in the mess.

Answer 1

Hello,

For personal Outlook.com, there are two separate things that often get mixed up:

Block list behavior: blocked senders and domains should route mail to Junk

Rules behavior: rules do not run on items already delivered to Junk

Outlook.com junk filtering happens ahead of rules, and rules only apply to mail delivered to the Inbox, not the Junk folder unfortunately, just as you already discovered.

Junk folder actually does work like the Deleted items folder. Emails in those folders are deleted permanently 30 days later automatically.

I am sorry, I wish I could give you a better answer, but this is quite a limitation by design.

Answer 2

To effectively block domains so that emails from them do not even reach your Junk folder, you can use the Tenant Allow/Block List feature in Microsoft Defender for Office 365. This feature allows you to block specific domains and email addresses, ensuring that messages from these senders are treated as high confidence spam and are not delivered to any folder, including Junk.

Here’s how to set it up:

1. Go to the Microsoft Defender portal at https://security.microsoft.com.
2. Navigate to Email & collaboration > Policies & rules > Threat policies > Rules section > Tenant Allow/Block Lists.
3. On the Tenant Allow/Block Lists page, select the Domains & addresses tab.
4. Click on Add, then select Block.
5. Enter the domains or email addresses you want to block, one per line (up to 20).
6. Optionally, set an expiration for the block entry and add a note for reference.
7. Save your changes.

By using the Tenant Allow/Block List, any emails from the blocked domains will not be delivered to your inbox or Junk folder, effectively reducing the spam you see.

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References:

• Allow or block email using the Tenant Allow/Block List
• Create sender blocklists for cloud mailboxes
• Set-MailboxJunkEmailConfiguration
• Create block entries for domains and email addresses
• Create block entries for spoofed senders