I have a situation where multiple users will need to access a workbook (want to avoid using the 'Share Workbook' option due to all the problems). I've determined that a possible solution to this is to get the workbook to automatically close after 15 minutes of inactivity.
I would also like a message to pop up after the 15 minutes which alerts the user that unless they click the 'okay' button, the workbook will close. If they click the button, I would like the counter to start over, and ideally if they don't click anything the workbook will automatically closer after a further 1 minute.
I have found some code online which I have used. The workbook successfully closes after a specified time but I can't figure out how to get the message box to pop up. Would appreciate any help, thanks!
Code I used is below:
In module 1:
Dim DownTime As Date
Sub SetTimer()
    DownTime = Now + TimeValue("0:15:00")
    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 
And in ThisWorkbook:
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
 
                        
Try the below
ShutDownprocedure: