A Chess Genius 7.2 user hit a compatibility wall. The engine, written by Richard Lang decades ago, runs only on 32-bit Windows systems. Windows 11 demands 64-bit software, so the program refuses to launch.
Lang also created Psion Chess, and he's historically been the sole developer for both engines. The user reached out to him directly asking if Chess Genius 7.2 could be converted to 64-bit. No response came back.
This is a familiar problem in chess computing. Strong older engines get stranded when operating systems evolve. Chess Genius 7.2 was competitive in its era, but it's essentially abandoned software now. Converting legacy 16-bit or 32-bit code to modern 64-bit architecture requires serious reverse engineering work. It's not a simple task, and it's not profitable, so it rarely happens.
The user's options are limited. Run Windows 7 in a virtual machine. Find an emulator. Or move on to a modern engine entirely. UCI (Universal Chess Interface) compatibility matters less here than the fundamental architecture problem.
This happens regularly in chess engine communities. Players hold onto older engines with sentimental attachment or nostalgic strength assessments, then discover they can't actually use them anymore. The gap between software preservation and modern computing keeps widening.