Apex Legends "CPU does not have POPCNT!" error means your PC isn't supported

Getting a “CPU does not have POPCNT!” error message when launching Apex Legends on your PC? Well, we hate to break this to you but it means that your processor isn’t supported by the game. If you’re seeing the POPCNT error, your PC most likely uses an old Intel CPU which isn’t built with the SSE4 instructions set.

Unsupported CPU
CPU does not have POPCNT!

While there are tools like POPCNT Emulator which developer ogurets built to run Quantum Break on pre-SSE4.2 CPUs, but Apex Legends is using Easy Anti-Cheat engine which means patching the game’s executable r5apex.exe binary will trigger the anit-cheat system and might get users banned by EA.

The solution would be a sophisticated loader, which starts the program in debug mode, circumventing all attempts to detect it (anti-debugging techniques) and patches the game in real time, in memory.
Or unpacking/decrypting the game, disabling anti-cheat and doing that every time a game update is released.
says ogurets

Perhaps, it’s best to upgrade the CPU on your PC to at-least meet the minimum system requirements of the game, if not the recommended config.