Outlook Rules stopped working automatically

Got it, Ryan. Since you only use Outlook on the web, the steps still apply but focus fully on server-side rules.

Here’s the process:

Sign in to Outlook on the web.

Go to Settings > Mail > Rules.

Delete any broken or old rules.

Click Add new rule, set your condition, then choose Move to folder.

Pick a folder you have permission to access and save the rule.

Test by sending a message that matches your condition.

If the rule still does not run, confirm your delegate access is set to Editor or higher on both the mailbox and the target folder. Microsoft documents that without proper folder permission, rules in delegated mailboxes fail to apply.

By the way, have you already tried creating a brand-new rule directly in Outlook Web, not editing an old one?

For reference: https://learn.microsoft.com/en-us/answers/questions/4628353/i-added-rules-to-the-delegated-mailbox-but-the-rul

Best regards,

Arlene D.

Thanks for the update, Ryan. Since new rules didn’t work, the problem is likely delegate permissions or mailbox corruption.

Check your delegate access is Editor or Owner for the mailbox and target folder.

If permissions are correct, remove the delegated mailbox from Outlook on the web, then add it back.

Recreate the rule in Outlook on the web and test.

If it still fails, contact Microsoft support to check for mailbox issues or hidden corruption.

Got it, Ryan. Thanks for clarifying.

To check or fix delegate access, the mailbox owner needs to do this:

Outlook on the web

• Owner signs in.
• Right click the Inbox, choose Sharing and permissions.
• Add your name, set permission level to Editor, then Save.

Classic Outlook for Windows

• Owner opens Outlook.
• Right click the Inbox, choose Properties, then Permissions tab.
• Add your name, set permission level to Editor or Publishing Editor, then OK.
• In File > Account Settings > Delegate Access, confirm you are listed with Editor rights.

Once permissions are set, have the owner sign in directly to the mailbox in Outlook on the web. Create one simple rule there (for example, move messages from your own address to a test folder). Send a test email to see if the rule runs.

This test shows if rules work for the mailbox itself. If they do, your delegate access is the issue. If not, the problem is with the mailbox rules, and the admin should check the mailbox rules quota in Exchange Online.

https://support.microsoft.com/en-us/office/manage-email-messages-by-using-rules-in-outlook-c24f5dea-9465-4df4-ad17-a50704d66c59

https://support.microsoft.com/en-us/office/set-up-rules-in-outlook-75ab719a-2ce8-49a7-a214-6d62b67cbd41?

Best regards,

Arlene D.

Hi Ryan, thanks for sharing the details. Are you using Outlook for Windows, Mac, or the web app?

Outlook rules for delegated mailboxes stop working if permissions or server-side settings change. Check that you still have Editor or Owner access, confirm the folder allows moves, and make sure your mailbox is not full. Recreate the rule in Outlook Web App to ensure it is server-side, as server-side rules run even if desktop Outlook is closed.

Best regards,

Arlene D.

Got it, Ryan. Thanks for clarifying. Let’s keep it simple.

To check or fix delegate access, the mailbox owner needs to do this:

Outlook on the web

• Owner signs in.
• Right click the Inbox, choose Sharing and permissions.
• Add your name, set permission level to Editor, then Save.

Classic Outlook for Windows

• Owner opens Outlook.
• Right click the Inbox, choose Properties, then Permissions tab.
• Add your name, set permission level to Editor or Publishing Editor, then OK.
• In File > Account Settings > Delegate Access, confirm you are listed with Editor rights.

Once permissions are set, have the owner sign in directly to the mailbox in Outlook on the web. Create one simple rule there (for example, move messages from your own address to a test folder). Send a test email to see if the rule runs.

This test shows if rules work for the mailbox itself. If they do, your delegate access is the issue. If not, the problem is with the mailbox rules, and the admin should check the mailbox rules quota in Exchange Online.

Best regards,

Arlene D.