Declare Function SendMessage Lib "user32" Alias "SendMessageA" _
  (ByVal hWnd As Long, ByVal Msg As Long, ByVal wParam As Long, _
  ByVal lParam As Long) As Long
 
Public Sub optimalWidth(lv As ListView)
  Dim t%
 
  On Error Resume Next
  For t = 0 To lv.ColumnHeaders.count - 1
    SendMessage lv.hWnd, &H101E, t, -1
  Next t
 
End Sub

Private Declare Ansi Function  SendMessage Lib "user32" Alias "SendMessageA" _
  (ByVal hWnd As Long, ByVal Msg As Long, ByVal wParam As Long, _
  ByVal lParam As Long) As Long
 
Public Sub optimalWidth(ByVal lv As ListView)
    Dim t As Integer
 
    For t = 0 To lv.Columns.Count - 1
      SendMessage(lv.Handle.ToInt64, &H101E, t, -1)
    Next 
 
  End Sub