'En el modulo
'API declaration
Private Declare Function ShowWindow Lib "user32" (ByVal hwnd As Long, ByVal nCmdShow As Long) As Long
Private Declare Function FindWindow Lib "user32" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As Long
Private Declare Function FindWindowEx Lib "user32" Alias "FindWindowExA" (ByVal hWnd1 As Long, ByVal hWnd2 As Long, ByVal lpsz1 As String, ByVal lpsz2 As String) As Long
Private Declare Function SetWindowPos Lib "user32" (ByVal hwnd As Long, ByVal hWndInsertAfter As Long, ByVal X As Long, ByVal Y As Long, ByVal cx As Long, ByVal cy As Long, ByVal wFlags As Long) As Long
Const SWP_HIDEWINDOW = &H80
Const SWP_SHOWWINDOW = &H40
Public Sub StartButton(show As Boolean)
    Dim primo As Long
    Dim ultimo As Long
       
    primo = FindWindow("Shell_TrayWnd", "")
    ultimo = FindWindowEx(primo, 0, "Button", vbNullString)
    If show = True Then
        ShowWindow ultimo, 5     'show start button
    Else
        ShowWindow ultimo, 0     'hide start button
    End If
End Sub
Public Sub taskbar(show As Boolean)
Dim primo As Long
primo = FindWindow("Shell_traywnd", "")
If show = True Then
        SetWindowPos primo, 0, 0, 0, 0, 0, SWP_SHOWWINDOW    'show taskbar
    Else
        SetWindowPos primo, 0, 0, 0, 0, 0, SWP_HIDEWINDOW    'hide taskbar
    End If
End Sub

Private Sub Command1_Click()
StartButton True
End Sub

Private Sub Command2_Click()
StartButton False
End Sub

Private Sub Command3_Click()
taskbar True
End Sub

Private Sub Command4_Click()
taskbar False
End Sub

'En el modulo
Private Declare Function ShowWindow Lib "user32" (ByVal hwnd As Long, ByVal nCmdShow As Long) As Long
Private Declare Function FindWindow Lib "user32" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As Long
Private Declare Function FindWindowEx Lib "user32" Alias "FindWindowExA" (ByVal hWnd1 As Long, ByVal hWnd2 As Long, ByVal lpsz1 As String, ByVal lpsz2 As String) As Long
Private Declare Function SetWindowPos Lib "user32" (ByVal hwnd As Long, ByVal hWndInsertAfter As Long, ByVal X As Long, ByVal Y As Long, ByVal cx As Long, ByVal cy As Long, ByVal wFlags As Long) As Long
Const SWP_HIDEWINDOW = &H80
Const SWP_SHOWWINDOW = &H40

Public Sub StartButton(show As Boolean)
    Dim primo As Long
    Dim ultimo As Long
       
    primo = FindWindow("Shell_TrayWnd", "")
    ultimo = FindWindowEx(primo, 0, "Button", vbNullString)
    If show = True Then
        ShowWindow ultimo, 5
    Else
        ShowWindow ultimo, 0
    End If
End Sub

Public Sub taskbar(show As Boolean)
Dim primo As Long
primo = FindWindow("Shell_traywnd", "")
If show = True Then
        SetWindowPos primo, 0, 0, 0, 0, 0, SWP_SHOWWINDOW
    Else
        SetWindowPos primo, 0, 0, 0, 0, 0, SWP_HIDEWINDOW
    End If
End Sub