These are example scenarios when this may occur: This problem occurs because the Office for Mac 2011 licensing file is missing or because the Installation ID for the license does not match the installation ID of the computer on which Office for Mac 2011 is installed. You receive this prompt even though the product is licensed. When you try to start any Office for Mac 2011 application, you are prompted to enter the product key and activate the program or to purchase the product online.
