This article is for Office for Mac 2011. Are you using Office on PC? See Using product keys with Office. Where do I find my Office for Mac 2011 product key? Once you have your product key, see Activate Office for Mac 2011. When you install or reinstall Microsoft Office, you are prompted to enter the product key. Office for Mac 2011 comes with a 25-character alphanumeric activation key that must be entered within 15 days of running any of the suite's applications for the first time. During that grace. Office for Mac 2011 product keys. My product key isn't working. First, make sure that you're entering the key correctly on the right site. If you aren't sure which site to use, you can enter your product key using the Virtual support agent (English only). If your product key is valid, the Virtual support agent provides a link to download Office. Office 2011 requires activation and is tied to your hardware so it might very well be that you need to reactivate Office 2011 after the HD change. The whole activation procedure is described in Office for Mac 2011 Activation and Product key Information (via archive.org). According to this document, the product key was mailed to you in a mail.
Microsoft Product Activation tries to reduce counterfeit software, and to make sure that Microsoft customers receive the software quality that they expect. The goal of Product Activation is to reduce a form of piracy known as 'casual copying' or 'softlifting.' Casual copying is a form of piracy characterized by the sharing of software between people in a way that infringes on the software's end user license agreement (EULA).
Activation is a new feature in Office Mac 2011. All previous versions of Office for Mac, other then trial, did not require Activation.
After you activate the software product, a specific product key is assigned to the computer hardware on which you installed the product. Product Activation is required to use the product. If you choose to click on the Activate Later button, the product will run for 15 days only. When launching an application it will remind you to activate with the following message 'You must activate your copy of Office for Mac within 15 days.'