With PTC Mathcad Express, you can try out the basic features of PTC Mathcad Prime before you purchase a licensed version of the product. Premium features of PTC Mathcad Prime are still locked, and are marked with a lock icon. An indicator bar beneath the Ribbon shows that you are running PTC Mathcad Express.
To purchase a license and make all the locked features available, click Upgrade.
To activate a newly acquired license, click Activate.