Contact WIRIS support directly. Explain that you lost a legitimate license key for MathType 7. Often, if you provide a proof of purchase (bank statement, old email with order ID), they will resend the key for free. If not, they may offer a steep discount (~40% off) for a new MathType 365 license.
MathType 7 uses a perpetual license (not subscription-based, unlike MathType 8+ for some platforms). product key mathtype 7
Pricing (approximate, as of 2025):
Even with a legitimate key, users encounter issues. Here are the top error messages and fixes. Contact WIRIS support directly