Fix ERR_INVALID_TOKEN or Invalid Product Key Error

Office product key redemption fails with error codes ERR_INVALID_TOKEN or ERR_MISSING_PARTNUMBER when attempting to activate at Office.com/setup. The activation page displays "Sorry, we can't find this product key in our database" or "Sorry, we can't set up your account right now."

The Fix

This usually happens because an older, perpetual Office product key (2010-2021) is being entered on Office.com/setup, which only accepts Microsoft 365 subscription keys. Use the correct redemption path for your product type.

For Microsoft 365 Business keys (starting with "N-"):

1. Go to https://admin.microsoft.com

2. Navigate to Billing > Your products

3. Click "Enter product key"

4. Sign in with your admin account

For retail Office 2016-2021 keys:

1. Go to https://account.microsoft.com/services

2. Sign in with the Microsoft account linked to your purchase

3. Locate your Office product

4. Click "Install Office" to download

5. Enter the key during installation, not at Office.com/setup

For volume license keys (MAK/KMS):

Contact your IT admin or use the Volume Activation Management Tool. These keys are activated through the Volume Licensing Service Center, not consumer portals.

If That Doesn't Work: Remove Conflicting Installations

Pre-installed Office trials can block new key activation.

1. Open Settings > Apps > Apps & features (Windows 10/11)

2. Search for "Office" or "Microsoft 365"

3. Uninstall all Office versions except your target installation

4. Restart the system

5. Reinstall Office from your download link

6. Enter the product key during setup

If That Doesn't Work: Clear License Cache

Run PowerShell as Administrator to check and repair activation.

# Check current license status
cscript "C:\Program Files\Microsoft Office\Office16\OSPP.VBS" /dstatus

Remove cached licenses
cscript "C:\Program Files\Microsoft Office\Office16\OSPP.VBS" /unpkey:XXXXX

Replace XXXXX with the last five characters of the installed product key shown in the /dstatus output. Adjust Office16 to your version (e.g., Office15 for 2013, Office14 for 2010).

Then trigger Office repair:

& "$env:ProgramFiles\Common Files\Microsoft Shared\ClickToRun\OfficeC2RClient.exe" /update user

Restart and re-enter your product key.

If That Doesn't Work: Registry Cleanup

Backup the registry (File > Export in regedit) before making changes.

1. Open regedit

2. Navigate to HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Common\Licensing\Cache

3. Delete all subkeys under Cache

4. Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\16.0\Registration

5. Delete all subkeys except {90160000-008F-0000-1000-0000000FF1CE} (the base Office installation)

6. Restart and attempt activation

Adjust 16.0 to match your Office version (15.0 for Office 2013, 14.0 for Office 2010).

Verify

Check activation status in PowerShell:

cscript "C:\Program Files\Microsoft Office\Office16\OSPP.VBS" /dstatus

Output should show LICENSE STATUS: ---LICENSED--- and your product name. Alternatively, open any Office application (Word, Excel), go to File > Account, and verify the product is activated with no error messages.

For Microsoft 365 subscriptions, confirm your subscription status at https://account.microsoft.com/services shows "Active" with the correct expiration date.