Since I recently started using BitVise as my SSH client on Windows machines I became quickly irritated by the beeping every time I punched in an invalid key combination. Since I had all my Windows sounds muted I figured it must be coming from command prompt (which is what BitVise uses). After a few minutes of digging around I managed to find the solution.
Open up your command prompt and enter:
net stop beep
And that’s all there is to it!