You cannot start a command line tool like appcmd.exe with browsing it from windows explorer.
The correct steps for star appcmd.exe like this:
1. Start\run and type cmd.exe (or start\run PowerShell)
2. Type cd c:\windows\system32\inetsrv (assuming you have installed Windows to c:\windows).
3. Type appcmd.exe for see the help or begin to use.