This seems to be odd bug, not impacting windows itself but some things like python. Can you check this code on your Win:

if %PATHEXT:~-1% == ";" (echo Bugged) else (echo Seems fine)

What it prints ?

Or just check the env var in System Info.
Software> Environment Variables
Find PATHEXT

Nah, loads of extensions there.

@melezorus34

yeah `echo %PATHEXT%` and figure out last char basically

The problem is that by default it should end by last EXT like ;WSC

For some reason on my PC it ends with ";", which allows executables without any extension, but also bugs python's which.

Might because you deleted some associaton manually.

You should be able to fix it via
Control Panel> System
At "Advanced" Tab press the button with env (at the bottom)

Bottom half of the window is SYSTEM vars and at there you can edit pathext variable.

@melezorus34 man I know this stuff. I just want to verify if it's because some common tool/language messes up. I do not touch this var because I do not need too :D