MicMute

/* 2>nul || title MicMute.bat by AveYo v2019.04.06
@echo off
goto :start

:: To undo, open CMD as admin and enter:
reg delete HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\AppKey\15 /f
reg delete "HKLM\SYSTEM\CurrentControlSet\Control\Keyboard Layout" /v "Scancode Map" /f

:start
:: Compile MicMute.cs snippet
mkdir %APPDATA%\AveYo 2>nul
pushd %APPDATA%\AveYo
del /f /q MicMute.exe >nul 2>nul
for /f "tokens=* delims=" %%v in ('dir /b /s /a:-d /o:-n "%Windir%\Microsoft.NET\Framework\*csc.exe"') do set "csc="%%v""
%csc% /out:MicMute.exe /target:winexe /platform:anycpu /optimize /nologo "%~f0"
if not exist MicMute.exe echo ERROR! Failed compiling c# snippet & timeout /t -1 & exit /b

:: Override APPCOMMAND_LAUNCH_MAIL to toggle MicMute
reg add HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\AppKey\15 /v ShellExecute /d "\"%APPDATA%\AveYo\MicMute.exe\"" /f

:: Override ScrollLock key to act as APPCOMMAND_LAUNCH_MAIL
echo YOU NEED TO RUN THE SCRIPT AS ADMINISTRATOR TO REMAP SCROLLLOCK TO LAUNCH_MAIL
reg add "HKLM\SYSTEM\CurrentControlSet\Control\Keyboard Layout" /v "Scancode Map" /d 0000000000000000020000006ce0460000000000 /t reg_binary /f
echo.

echo Now Sign-Off to apply ScrollLock / Launch Mail = MicMute
timeout /t 5 >nul

:: Done!
exit/b

MicMute.cs */
using System;
using System.Runtime.InteropServices;
using System.Reflection;

[assembly:AssemblyTitle("MicMute")]
[assembly:AssemblyCompanyAttribute("AveYo")]
[assembly:AssemblyVersionAttribute("2019.04.06")]

namespace MicMute
{
  class Program
  {
    private const int WM_APPCOMMAND = 0x319;
    private const int APPCOMMAND_MICROPHONE_VOLUME_MUTE = 0x180000;
    [DllImport("user32.dll", SetLastError = false)]
    public static extern IntPtr GetForegroundWindow();
    [DllImport("user32.dll", SetLastError = false)]
    public static extern IntPtr SendMessageW(IntPtr hWnd,int Msg,IntPtr wParam,IntPtr lParam);
    static void Main(string[] args)
    {
      try
      {
        IntPtr h = GetForegroundWindow();
        SendMessageW(h,WM_APPCOMMAND,IntPtr.Zero,(IntPtr)APPCOMMAND_MICROPHONE_VOLUME_MUTE);
      }
      catch (Exception)
      {
      }
    }
  }
}
/*_*/