SoloCodigo

1. Agrega un boton Command en tu formulario

2. Agrega un formulario de MODULO y copia lo siguiente:

Public Declare Function GetSystemMenu Lib "user32" (ByVal hwnd As Long, ByVal bRevert As Long) As Long
Public Declare Function RemoveMenu Lib "user32" (ByVal hMenu As Long, ByVal nPosition As Long, ByVal wFlags As Long) As Long
Public Const SC_MOVE = &HF010&
Public Const MF_BYCOMMAND = &H0&

3. En el control Button, coloca el siguiente codigo:
Private Sub Command1_Click()
    lhSysMenu = GetSystemMenu(Me.hwnd, False)
    lRetVal = RemoveMenu(lhSysMenu, SC_MOVE, MF_BYCOMMAND)
End Sub


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