Hello, @John Peter
Welcome to the Microsoft Q&A platform!
Here are the steps to enable archiving in Outlook:
Enable AutoArchive in Outlook:
- Open Outlook and go to File > Options.
- In the Outlook Options window, select Advanced.
- Under AutoArchive, click AutoArchive Settings.
- Check the box for Run AutoArchive every n days and specify how often you want AutoArchive to run.
- Choose other options as needed, such as deleting old items instead of archiving them.
- Click OK to save your settings.
Refer to: Archive older items automatically - Microsoft Support.
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Enable Archive Mailbox in Microsoft 365:
- Sign in to the Exchange admin center (EAC).
- Navigate to Recipients > Mailboxes.
- Select the user whose mailbox you want to enable for archiving.
- In the flyout pane, select Others, and under Mailbox archive, click Manage mailbox archive.
- Turn on Mailbox archive and click Save. It might take a few moments to create the archive mailbox.
Refer to: Enable archive mailboxes for Microsoft 365 | Microsoft Learn
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Should you need more help on this, you can feel free to post back.
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Thank you for your support and understanding.
Best Wishes,
Alex Zhang