Using a counterfeit product key violates Microsoft’s Software License Terms. While the company rarely sues individual home users, businesses and educational institutions have faced audits and fines. At a minimum, you are committing software piracy, which is illegal in most countries.

If you're part of a non-profit organization, you may be eligible for a free product key through Microsoft's non-profit program.

If you have a valid school email address (e.g., .edu), visit Microsoft’s Office 365 Education page. Many institutions provide Office 365 A1 for free, which includes the desktop versions of Word, Excel, PowerPoint, and more. That’s essentially Office Professional Plus for free.

Check your eligibility at: microsoft.com/en-us/education/products/office

Genuine Microsoft Office receives regular security updates. Pirated copies either block Windows Update or are excluded from receiving patches. That leaves you vulnerable to exploits like CVE-2021-40444 (a zero-day remote code execution flaw) or memory corruption vulnerabilities found in Office 2021.