Overview

If a user’s Archive folder was previously visible and has suddenly disappeared, this usually indicates a sync issue, view corruption, or a temporary Exchange Online provisioning or caching problem. This guide outlines the recommended troubleshooting steps to restore visibility of the Archive mailbox and folder in both Outlook and Outlook Web App (OWA).

Step 1 - Confirm the Archive Mailbox Is Still Enabled

1. Log in to the Exchange Admin Center (EAC): https://admin.exchange.microsoft.com

2. Go to Recipients → Mailboxes.

3. Select the affected user.

4. Under Mailbox Settings, locate the Archiving section.

5. Ensure Archiving is still Enabled.

– If it shows Disabled, re-enable it.

– If it is already enabled, do not disable/re-enable immediately — instead, proceed to Step 2.

Step 2 - Verify in PowerShell That the Archive Mailbox Exists

1. Connect to Exchange Online PowerShell.

2. Run the following command:

Get-Mailbox -Identity "User Name" | Select ArchiveStatus, ArchiveName, ArchiveGuid

3. Check the ArchiveStatus value:

– If it shows Active, the archive mailbox still exists.

– If it shows None, the archive mailbox was removed or never provisioned.

4. If Active but the folder is missing, continue to Step 3.

Step 3 - Check Outlook Web App (OWA)

1. Have the user log in to Outlook on the Web at https://outlook.office.com.

2. Scroll through the left-hand folder list — the Archive folder may appear lower in the list or under “More Folders.”

3. If it is still missing:

– Try a browser refresh (Ctrl + F5).

– Sign out, clear cache, and sign back in.

4. If the Archive appears in OWA but not in Outlook desktop, the issue is local to Outlook — proceed to Step 4.

Step 4 - Check Outlook Folder Cache and Connection

1. In Outlook, go to File → Account Settings → Account Settings.

2. Select the Microsoft 365 account and click Change → More Settings → Advanced.

3. Confirm Use Cached Exchange Mode is enabled.

4. Under the Mail to keep offline slider, ensure All is selected.

5. Restart Outlook and wait several minutes for folders to resync.

6. If still missing, hold Ctrl and right-click the Outlook icon in the system tray → choose Test Email AutoConfiguration, then run the test to ensure it connects to the right mailbox.

Step 5 - Rebuild the Folder List in Outlook

Sometimes the folder tree becomes corrupted in the local cache.

1. Close Outlook.

2. Navigate to:

%localappdata%\Microsoft\Outlook

3. Locate and delete the OST file for the user’s account (this only deletes the local cache, not the data).

4. Reopen Outlook — it will rebuild the folder structure from Exchange Online.

5. Allow time for synchronization; the Archive folder should reappear if it exists in Exchange.

Step 6 - Confirm Retention Policies Are Still Applied

1. In the Microsoft Purview Compliance Portal, go to Data Lifecycle Management → Retention Policies.

2. Make sure the user’s mailbox is still included in a policy that contains “Move to Archive” or similar tags.

3. If removed, re-add the user to the policy and allow several hours for Exchange to reapply it.

Step 7 - Check for Secondary Archive or GUID Mismatch (Advanced)

In rare cases, the archive GUID may have changed (for example, after a mailbox restore or migration).

1. Run:

Get-Mailbox -Identity "User Name" | FL ArchiveGUID, ArchiveDatabase

2. Compare this with the user’s Outlook profile logs (if available) — if Outlook references a different archive GUID, recreate the profile (Step 8 below).

Step 8 - Recreate the Outlook Profile

If the archive appears in OWA but not in Outlook, or if the local cache rebuild did not help:

1. Close Outlook.

2. Open Control Panel → Mail → Show Profiles.

3. Click Add to create a new profile.

4. Reconnect the Microsoft 365 account.

5. Launch Outlook and verify the Archive folder appears.

Step 9 - Verify From Another Device

If possible, sign into the same mailbox from another device or browser:
- If the Archive folder appears there, the problem is local to the user’s computer.
- If it is missing everywhere, contact Microsoft 365 Support to verify the archive mailbox’s integrity.

Summary

If an Archive folder disappears:
- Confirm the Archive mailbox is still active in Exchange Online.
- Check in OWA first — this confirms whether the issue is server-side or client-side.
- Rebuild Outlook cache or recreate the profile if it’s a local sync issue.
- Verify retention policies and archive GUIDs if it remains missing.

In most cases, simply clearing the Outlook cache or rebuilding the OST resolves the issue.