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Invalid product key errors in Microsoft Office
Provides a solution to help resolve this validation error in Microsoft Office 2010: "This is not a valid Office Product key."
Activate Office 2010 programs - Word - Office.com
To activate an Office 2010 program, you must enter your 25-digit product key, if you haven't already done so during Setup.
Activate Office 2007 - Word - Office.com
To activate an Office 2007 program, you must enter your 25-digit product key, if you haven't already done so during Setup.
Activate Office 2013 programs - Word - Office.com
To activate an Office 2013 program, you must enter your 25-digit product key, if you haven't already done so during Setup.
Activate or register programs in the Microsoft Office System - Word - Office.com
Show All Hide All Applies to Microsoft Office System To continue to use all the features of your product, you need to activate your software. Microsoft Product Activation is an