my outlook is deemed unlicenced despite having a current subscription

Do not install another Outlook version yet; first reactivate the existing installation with the Microsoft account that owns the subscription, because an activation failure disables features such as replying and forwarding.^1^

Restore the licence

1. Close Outlook and all other Office applications.
2. Open the Microsoft Services & subscriptions page from Microsoft’s activation article, then sign in with the account used to purchase Microsoft 365.
3. Confirm that Microsoft 365 appears under Subscriptions as active.
4. Reopen Outlook and select File → Office Account.
5. If Outlook shows a different account:
   • Select Sign out.
   • Close and reopen Outlook.
   • Sign in with the exact account shown on the Services & subscriptions page.

Having the subscription under one Microsoft account while Office is signed in with another prevents activation.^1^

If it remains unlicensed

Run Microsoft’s Microsoft 365 activation troubleshooter from the same affected PC. It opens through the Windows Get Help application and requires Windows 10 or later.^1^

Then check for conflicting installations:

1. Open Control Panel → Programs → Programs and Features.
2. Search the installed-program list for Office.
3. If multiple Office versions are installed, uninstall only the version you do not use.
4. Restart Windows and sign in to Office again.

If only one installation exists, repair it instead of reinstalling:

• Windows 11: Right-click Start → Installed apps → Microsoft 365 → … → Modify → Online Repair → Repair.
• Windows 10: Right-click Start → Apps and Features → Microsoft 365 → Modify → Online Repair → Repair.

Online Repair is more complete than Quick Repair and repairs the entire Office suite.^2^

Protect existing email before any reinstall

Installing another version is unnecessary for this licensing problem and can create an activation conflict if both copies remain installed. A reinstall should therefore be the last step.

For additional protection, export a backup from classic Outlook if its menus remain available:

1. Select File → Open & Export → Import/Export.
2. Select Export to a file → Outlook Data File (.pst).
3. Select the email account and enable Include subfolders.
4. Save the PST under a new filename on a local drive or external drive—not in a OneDrive-synced folder.

A PST export creates a copy; it does not remove the original email, contacts, or calendar items from Outlook.^3^

If activation, the troubleshooter, and Online Repair all fail, contact Microsoft Support so the subscription’s activation status can be checked. Do not uninstall Outlook until either the mailbox is confirmed available through webmail or a PST backup has been created.

References

1. Unlicensed Product and activation errors in Office | Microsoft Support
2. Repair an Office application
3. Export emails, contacts, and calendar items to Outlook using a .pst file | Microsoft Support