Office says "Product Deactivated" or "Unlicensed Product"

First, always. Half of these are exactly what the banner says.

1. Check the user in the admin centre under Users → Active users → Licences and apps, and confirm both that a licence is assigned and that the Office apps are enabled within it.

2. Check the subscription itself has not lapsed or run out of seats under Billing → Your products.

3. If a licence was removed and re-added, allow up to 24 hours, or force the client to re-check once assigned.

   Re-assigning a licence does not push anything to the client. The client re-checks on its own schedule, and the steps below are how to make it do so now.

The licence is definitely assigned but the client will not accept it.

1. Close all Office applications.

2. List the installed licences so you know what you are removing.

   Command PromptCopy

   cd 'C:\Program Files\Microsoft Office\Office16'cscript ospp.vbs /dstatus

3. Clear the cached licence tokens.

   PowerShellCopy

   Remove-Item "$env:LOCALAPPDATA\Microsoft\Office\Licenses" -Recurse -Force -ErrorAction SilentlyContinueRemove-Item "$env:LOCALAPPDATA\Microsoft\Office\16.0\Licensing" -Recurse -Force -ErrorAction SilentlyContinue

   This is where the subscription licence lives on a per-user basis. A token issued to an identity that has since changed will keep failing quietly, and no amount of signing in replaces it while it is still on disk.

4. Clear the shared computer licensing token if this is a session host.

   PowerShellCopy

   Get-ChildItem "$env:LOCALAPPDATA\Microsoft\Office\16.0\Licensing" -ErrorAction SilentlyContinue | Remove-Item -Recurse -Force

5. Remove the Office credentials as well, then start Word and sign in.

   PowerShellCopy

   cmdkey /list | ForEach-Object { if ($_ -match 'Target:\s*(MicrosoftOffice\S+)') { cmdkey /delete:$($Matches[1]) } }

cscript 'C:\Program Files\Microsoft Office\Office16\ospp.vbs' /dstatus

Several machines on the same network are affected — the fault is the network, not the machines.

1. Test the endpoints Office actually uses.

   PowerShellCopy

   'login.microsoftonline.com','activation.sls.microsoft.com','ols.officeapps.live.com' |  ForEach-Object { Test-NetConnection $_ -Port 443 -InformationLevel Quiet |    ForEach-Object -Begin {} -Process { "$_" } }

2. Check for TLS inspection on the firewall. A proxy that re-signs certificates breaks activation unless its root is trusted by the machine, and the error given is this one.

   The client is not told that a certificate was replaced — it simply fails to establish trust and reports the licence as unavailable. This is why activation can be the only thing broken on an otherwise working network.

3. Check the machine-wide proxy, which services use even when the browser is fine.

   Command PromptCopy

   netsh winhttp show proxy

4. Exempt the Microsoft 365 endpoints from inspection rather than from the firewall entirely.