If you are looking for this software today, here is the current status: Official Alternatives Mathcad Prime : The current supported version is PTC Mathcad Prime Free Version Mathcad Express
is a limited version of Mathcad Prime that remains free to use forever after a 30-day full-feature trial. Legacy Conversion : Users with old files (from Mathcad 14) can use the Mathcad Prime Converter to update them to the new format. PTC Community Installation for Existing Owners
Official support and downloads for Mathcad 14 ended after December 31, 2021. PTC, the developer, no longer sells or distributes legacy versions (Mathcad 11 through 15) due to third-party component licensing changes. PTC Community
If you already possess the original installation media or a valid license, keep these technical requirements in mind for modern systems: Mathcad 14 legacy software installation - PTC Community