Yes, the string with spaces must be enclosed in double quotes. But when a programmer calls CreateProcess(), he himself puts double quotes or calls CommandLineToArgvW().

subprocess.list2cmdline() is always called and can spoil the launch string.

I propose to add an additional argument list2cmdline=False in subprocess.run() to disable this function.

subprocess.run(['"program path"', '/param="space space"'], list2cmdline=False)

subprocess.run('"program path" /param="space space"', list2cmdline=False)