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If it points you to check the log files, it'll also tell you where they are.
What does it tell you?
Maybe a screenshot...?
And of course, you can have a look here: https://community.ptc.com/t5/PTC-Mathcad-Installation/All-About-Mathcad-Software-Installation/td-p/706433 to see if there's some information that can help you solve your problem.
Success!
Luc