When PTC released Mathcad Prime 1.0, they completely rewrote the code. While Prime is more modern, long-time users complained it was slower, missing features (like symbolic solving on the fly), and had a clunky ribbon interface. Thus, version 14 remains a "cult classic."
If you are looking for that classic Mathcad experience without the high price tag or the risk of outdated software, here is the current landscape: Mathcad 14 Free Download
This is the only official free version currently available. It is a "light" version of the modern Mathcad Prime . It never expires and allows you to use basic math functions, though advanced features (like symbolics and programming) are locked. When PTC released Mathcad Prime 1
An engineering student downloaded a "free Mathcad 14" from a torrent site. The installer worked, but Windows Defender later flagged winlogon.exe corruption. The student had to wipe their hard drive. The calculation they needed to check? A simple beam deflection – which they could have done for free in Octave or SMath Studio (see below). It is a "light" version of the modern Mathcad Prime