' Yo incluí este codigo en un form
Option Compare Database
Option Explicit

    Private Declare Function IsWindowVisible Lib "user32" (ByVal hwnd As Long) As Long

    Dim dwReturn As Long

    Const SW_HIDE = 0
    Const SW_SHOWNORMAL = 1
    Const SW_SHOWMINIMIZED = 2
    Const SW_SHOWMAXIMIZED = 3

    Private Declare Function ShowWindow Lib "user32" (ByVal hwnd As Long, _
        ByVal nCmdShow As Long) As Long

Private Sub demofA()

    msgbox fAccessWindow("Show", False, True)

End Sub

Public Function fAccessWindow(Optional Procedure As String, _
                Optional SwitchStatus As Boolean, _
                Optional StatusCheck As Boolean) As Boolean
    If Procedure = "Hide" Then
        dwReturn = ShowWindow(Application.hWndAccessApp, SW_HIDE)
    ElseIf Procedure = "Show" Then
        dwReturn = ShowWindow(Application.hWndAccessApp, SW_SHOWMAXIMIZED)
    ElseIf Procedure = "Minimize" Then
        dwReturn = ShowWindow(Application.hWndAccessApp, SW_SHOWMINIMIZED)
    End If

    If SwitchStatus = True Then
        If IsWindowVisible(hWndAccessApp) = 1 Then
            dwReturn = ShowWindow(Application.hWndAccessApp, SW_HIDE)
        Else
            dwReturn = ShowWindow(Application.hWndAccessApp, SW_SHOWMAXIMIZED)
        End If
    End If

    If StatusCheck = True Then
        If IsWindowVisible(hWndAccessApp) = 0 Then
            fAccessWindow = False
        ElseIf IsWindowVisible(hWndAccessApp) = 1 Then
            fAccessWindow = True
        End If
    End If

End Function

' En mi caso particular directamente oculto la ventana sin realizar control alguno, pero
' como podesver en las declaraciones (arr) lo podes hacer si lo necesitas
Private Sub Form_Load()
   dwReturn = ShowWindow(Application.hWndAccessApp, 0)
End Sub