how to recover lost activation key

When you first activated your Office licence, that licence should have become associated to your Microsoft Account as a digital licence online and it is from there that you can install Office on your new PC without the need for a product key:

https://account.microsoft.com/services/

Hello,

Whether you need the key depends on how Office was purchased:

A) Microsoft 365 subscription, or a retail Office key (2016/2019/2021/2024) that was redeemed

The licence was linked to your Microsoft account when it was first activated, so no key is needed:

1. Go to https://account.microsoft.com/services and sign in with the same Microsoft account used originally.
2. Find your Office product and select Install.
3. When Office asks to activate, sign in with that account. For one-time purchases the product card may also show View product key.
4. One-time-purchase licences are for one PC, so uninstall Office from the old computer if it is still in use.

B) Office came preinstalled on the old computer (OEM)

OEM licences are tied to that device and can't be transferred to a new computer, so a new licence is required.

C) The key was never linked to an account

Microsoft can't look up unlinked keys. Check the order confirmation email (search for "product key" or the store's name), your order history with the retailer, or the physical card/box.

If the old PC still works, you can see the last 5 characters of the installed key (useful for matching against your records) from an elevated Command Prompt:

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

Note: Office 2016 and Office 2019 reached end of support on October 14, 2025, so for a new PC Microsoft 365 or Office 2024 is the supported option.

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