Find your Product Key for Office 2010
This article is for Office 2010. Got another version? Try one of these:
When you install Office, you might be prompted to enter a 25-character product key.
If you downloaded Office from an online store, the product key should be in your email receipt.
If you didn’t get a receipt, search your email for Microsoft or the name of the company where you bought Office. Check all mail folders including the Junk folder.
If Office came with a box, card, or disc, look on the card or the packaging.
If the product key isn't there, read the instructions on the package. You might be directed to Office.com/getkey for your product key.
If Office came with your computer, look on the Certificate of Authenticity.
How to replace a lost or damaged Microsoft Office product key
If you purchased Office online and downloaded it or if Office is associated with a Microsoft account, you might be able to get your product key online. Go to your account page and sign in with your Microsoft account. Your account page will show you your product key.
If you lose your product key and have a valid proof of purchase, contact Microsoft support for help.