Without "io.mac", we have *no* idea what this code does!
The use of the 16-bit bx register might suggest dos code. I guess M$ made good on their threat to drop dos support in win64 - I really thought they'd back down on that. Guess not. That's just a guess...
If that's the problem, write some 64-bit code. Or win32 code??? I suppose that'll still run(?). Or install some sort of "dosbox" emulator. (I think there's one here at SF?) Or install a "dual boot" system, with dos as an option.
Best of all would be to escape your MicroSerfdom and graduate to Linux! (but dos code won't run there, either, without "dosemu").
Best,
Frank