How To Disable Close Button in Excel: Getting a Handle on hWnd

I know, right? The UserForms in Excel are actually of the Windows class ThunderDFrame, which is the class for all UserFroms in Microsoft Office applications after 2002 (it was “ThunderXFrame” before that). I’ve looked online for a good explanation for the name but haven’t really found anything. Either way you’ll need to pass that into the first argument of FindWindow whenever you need a UserForm’s handle.

How To Disable Close Button in Excel Using VBA

Important: Always provide at least one clear and accessible way for the user to close the form safely.

Rather than interrupting the user with unnecessary message boxes after they click the close button, a cleaner and more user-friendly approach is to disable or hide the close button altogether. This ensures a smoother experience and prevents confusion. Here’s how you can achieve this with VBA.

By proactively controlling the form’s behavior, you can streamline functionality while maintaining a professional and intuitive user interface.

'//Find the userform's Window
Private Declare Function FindWindow Lib "user32" _
        Alias "FindWindowA" ( _
        ByVal lpClassName As String, _
        ByVal lpWindowName As String) As Long

'//Get the current window style
Private Declare Function GetWindowLong Lib "user32" _
        Alias "GetWindowLongA" ( _
        ByVal hWnd As Long, _
        ByVal nIndex As Long) As Long

'//Set the new window style
Private Declare Function SetWindowLong Lib "user32" _
        Alias "SetWindowLongA" ( _
        ByVal hWnd As Long, _
        ByVal nIndex As Long, _
        ByVal dwNewLong As Long) As Long

Const GWL_STYLE = -16
Const WS_SYSMENU = &H80000

Private Sub UserForm_Initialize()
   Dim hWnd As Long, lStyle As Long

   If Val(Application.Version) >= 9 Then
      hWnd = FindWindow("ThunderDFrame", Me.Caption)
   Else
      hWnd = FindWindow("ThunderXFrame", Me.Caption)
   End If

   '//Get the current window style and turn off the Close button
   lStyle = GetWindowLong(hWnd, GWL_STYLE)
   SetWindowLong hWnd, GWL_STYLE, (lStyle And Not WS_SYSMENU)
End Sub

Bonus Tip: You can prevent the user from being able to close the window with Alt-F4 using this code as well:

Private Sub UserForm_QueryClose(Cancel As Integer, CloseMode As Integer)
      If CloseMode = vbFormControlMenu Then
        Cancel = True  
    End If
End Sub

That’s all for now!