En um módulo declaramos :

Declare Function mciSendString Lib "winmm.dll" Alias _
"mciSendStringA" (ByVal lpstrCommand As String, ByVal _
lpstrReturnString As String, ByVal uReturnLength As Long, _
ByVal hwndCallback As Long) As Long

Y luego para abrir la puerta :

dim res as long, returnstring as string*127
res = mcisendstring("set CDAudio door open", returnstring, 127, 0)

Y para cerrarla :


dim res as long, returnstring as string*127
res = mcisendstring("set CDAudio door closed", returnstring, 127, 0)