MATHCAD 15 installation on a new machine and expired license.
Hello everyone!
I have been using MATHCAD for decades, and since 2015 I have been working hard on MATHCAD 15 which I am enthusiastic about and continue to use. In view of a crash of the more than ten years old system on which it is installed, I tried to install MATHCAD 15 on a new machine, using the version stored on a pendrive. After installation and launch, it asks me for the license that I downloaded from the 2018 email attachment when I requested a new license. Unfortunately it is not recognized. How to overcome this obstacle? Thanks in advance for helping me.
Greetings,

