Hello @Shadid, Yousri A,
Good day! Thank you for posting your valuable question on Microsoft Q&A forum.
Based on your description, it sounds like you're able to view the online archive for your primary mailbox, but not for your shared mailbox in the New Outlook for Windows. Please let me know if I’ve misunderstood any part of your situation.
To investigate this issue, here are the recommended steps:
1.Identify Your Microsoft 365 Administrator
These steps require access to the Microsoft 365 Admin Center and must be performed by someone with the appropriate admin role - typically a Global Administrator or Exchange Online Administrator.
If you're unsure who holds this role in your organization, you can refer to this guide: How do I find my Microsoft 365 admin? - Microsoft Support.
2.Enable Online Archive via Exchange Admin Center (EAC)
- Sign in to the Exchange Admin Center: https://admin.exchange.microsoft.com
- In the left pane, go to Recipients > Mailboxes > Click on the mailbox you want to enable archiving for.
- In the flyout pane, scroll to Others > Click Manage mailbox archive.

- Toggle the switch "Mailbox archive status" to On > Click Save.
- Provisioning might take a little while. Once enabled, the mailbox will show Archive status: Enable.
- In Outlook, the user will see a new mailbox tree called Online Archive – [MailboxName]

3.Check Full Access Permissions
Even if the archive is enabled, the user must have full access to both the shared mailbox and its archive.
- Go to Exchange Admin Center.
- Navigate to Recipients > Mailboxes.
- Select the shared mailbox.
- Under Mailbox Delegation, confirm that your email account is listed under Full Access.
For related documents, please check:
If you've tried all the steps but still can't see the In-Place/Online Archive mailboxes, then this feature may not fully support for your New Outlook, you can check at: Microsoft 365 Roadmap | Microsoft 365
Please let me know if you need any further assistance or clarifications. Thank you for reaching out!
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