If you can't open an application, go to, scroll to the to the Office for Mac updates section, choose the latest update available. If you can, open an application like Word and click Help > Check for Product updates. In many cases, updating Office will fix the problem. In the Get Started wizard, click Sign in to an existing Office 365 subscription, and sign in with the email address that's associated with Office. Open an Office application and click Activate Now. Instead, sign in with the email address that's associated with Office.
If you have an Office 365 subscription, you can't use your product key to activate Mac 2011. Note: If your copy of Office came with a PIN instead of a product key, go to and enter your PIN to get your product key.
