In Outlook and Outlook.com, junk email is filtered automatically, but it cannot be completely prevented from arriving. The best that can be done is to make Outlook more aggressive and ensure that anything identified as junk is diverted away from the Inbox and then deleted without being seen.
To make junk filtering stricter and hide these messages as much as possible:
- Increase junk protection level in Outlook (classic desktop)
- In Outlook, select Home.
- In the Delete group, select Block, then Junk E-mail Options.
- On the Options tab, choose a higher level such as High or Safe Lists Only.
- High catches more junk but may occasionally move legitimate mail to Junk E-mail.
- Safe Lists Only is most restrictive and treats anything not on Safe Senders/Recipients as junk.
- Optionally, enable Permanently delete suspected junk email instead of moving it to the Junk E-mail folder if the goal is never to see these messages. This is risky because it removes the chance to recover messages that are misclassified.
- Use the Blocked Senders list
- In Outlook, on the Home tab, in the Delete group, select Block, then Junk E-mail Options.
- On the Blocked Senders tab, select Add.
- Enter specific email addresses or domains that frequently send unwanted content (for example,
someone@example.com or @example.com).
- Select OK and Apply.
Messages from these senders will always be treated as junk and moved to Junk E-mail (or deleted if the permanent delete option is enabled).
- Adjust junk settings in Outlook on the web/Outlook.com
If using Outlook.com or Outlook on the web with the same account:
- At the top of the screen, select Settings > Mail.
- Go to Junk email or Block or allow (depending on the interface).
- Ensure Automatically filter junk email is selected so that junk filtering is enabled.
- Under Blocked senders and domains, add addresses or domains that send offensive content.
- Under Safe senders and domains, add only trusted senders so legitimate mail is less likely to be filtered.
- (Outlook.com) Temporarily switch junk handling mode to reset behavior
If Outlook.com junk filtering seems ineffective, one known workaround is:
- In Outlook.com, go to Settings > Mail > Junk email.
- Set Incoming mail handling to Strict and save.
- Sign out of Outlook.com.
- Sign back in, return to Settings > Mail > Junk email, and set Incoming mail handling back to Standard.
- Save changes and wait a few hours for filtering behavior to stabilize.
- Manage subscriptions and marketing mail (Outlook.com)
For newsletters or marketing lists that are not strictly spam but are unwanted:
- In Outlook.com, select Settings.
- Select Mail, then Subscriptions.
- From Your current subscriptions, select unwanted senders and choose Unsubscribe or use the three dots (…) to Block the sender.
- Use Safe Senders to protect legitimate mail
To reduce the chance of losing good email when junk filtering is set to High or stricter:
- In Outlook on the web/Outlook.com, go to Settings > Mail > Junk email.
- Under Safe senders and domains, select Add safe sender and add important contacts and domains.
- Save changes.
These steps cannot stop all junk from being sent to the account, but they ensure that most offensive messages are filtered away from the Inbox and, if desired, automatically deleted so they are not visible in the Junk folder.
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