Instead of using a free product key, consider the following alternatives:
: MathType is available as a free-to-install add-in for Word and PowerPoint Online through the Microsoft Marketplace .
Allows you to draw equations on a touch screen or with a mouse, which the software then converts into digital text. Format Support: Full support for TeX, LaTeX, and MathML.
Fake: Many "key generator" programs are actually wrappers for malware. Key Features of MathType 7.4.4.516