Option Explicit
Private Sub Workbook_Open()
    Dim wb As Workbook
    Set wb = ThisWorkbook
    On Error GoTo ErrorHandler
    Application.DisplayAlerts = False
    Application.ScreenUpdating = False
    If Not wb.MultiUserEditing Then
        wb.SaveAs _
            Filename:=wb.FullName, _
            AccessMode:=xlShared
    End If
    wb.KeepChangeHistory = True
    wb.ChangeHistoryDuration = 30
    wb.HighlightChangesOptions _
        When:=xlAllChanges
    wb.HighlightChangesOnScreen = True
    wb.ListChangesOnNewSheet = True
    wb.Save
CleanExit:
    Application.DisplayAlerts = True
    Application.ScreenUpdating = True
    Exit Sub
ErrorHandler:
    Application.DisplayAlerts = True
    Application.ScreenUpdating = True
    MsgBox _
        "Error Track Changes:" & vbCrLf & _
        Err.Number & " - " & Err.Description, _
        vbExclamation, _
        "Track Changes"
End Sub