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Related topics:
https://community.ptc.com/t5/PTC-Mathcad/Installing-MC-14-with-Windows-10/td-p/119501
https://community.ptc.com/t5/PTC-Mathcad/Mathcad-14-0-3-0-error-1904-install-ocx-in-windows-7-64-bits/td-p/17764