Solved
Is it mandatory to use prime 10
Is Mathcad prime 9000 still working? Is it mandatory to use prime 10?
Why I'm having this message ?
It's not mandatory to use Prime 10.
It means that your license (if you had one) for Prime 9 has expired. Note that licensing is on subscription base. You have to pay a yearly fee in order to get your license period extended.
Success!
Luc