Close and Saved after 5 mins of inactivity code not saving

Hi,

The below code is supposed to save and close an excel spread sheet after 5 mins of inactivity,however it just closes and doesnt save. Can anyone tell me how to fix this?

Many thanks

This Workbook:

Private Sub Workbook_Open()
Call SetTimer
End Sub
Private Sub Workbook_BeforeClose(Cancel As Boolean)
Call StopTimer
End Sub
Private Sub Workbook_SheetCalculate(ByVal Sh As Object)
Call StopTimer
Call SetTimer
End Sub
Private Sub Workbook_SheetSelectionChange(ByVal Sh As Object, _
ByVal Target As Excel.Range)
Call StopTimer
Call SetTimer
End Sub


Moduel 1:

Dim DownTime As Date
Sub SetTimer()
DownTime = Now + TimeValue("00:05:00")
Application.OnTime EarliestTime:=DownTime, _
Procedure:="ShutDown()", Schedule:=True
End Sub
Sub StopTimer()
On Error Resume Next
Application.OnTime EarliestTime:=DownTime, _
Procedure:="ShutDown()", Schedule:=False
End Sub
Sub ShutDown()
Application.DisplayAlerts = False
With ThisWorkbook
.Saved = True
.Close
End With
End Sub