How to re-register the STEP-FOUR Frässoftware V4?

1. Delete the file REGISTER.SET from the installation directory.
2. Start Frässoftware V4 by double-clicking on s4pro.exe in the installation directory.
3. Enter your personal data, serial number and product ID.
4. Confirm the settings with “OK”.

Source: English translation of Laumat GmbH: FAQ DOS Fräsen V4: Wie kann man die Software neu registrieren?.