MS Access Idle Time Macro

I'm trying to close the database after so much time in idle due to the amount of users wanting on the database.  Here is a code I pulled from the Microsoft office website but there are some additions I would like to make.  This code works fine but I would like it to have a message box after 5 minutes to say Yes or No to close the database.  If the message box stays open and the user doesn't select either option, the database will wait another 3 minutes then close.

Here is what I have:
Private Sub Form_Timer()
         ' IDLEMINUTES determines how much idle time to wait for before
         ' running the IdleTimeDetected subroutine.
         Const IDLEMINUTES = 5

         Static PrevControlName As String
         Static PrevFormName As String
         Static ExpiredTime

         Dim ActiveFormName As String
         Dim ActiveControlName As String
         Dim ExpiredMinutes

         On Error Resume Next

         ' Get the active form and control name.

         ActiveFormName = Screen.ActiveForm.Name
         If Err Then
            ActiveFormName = "No Active Form"
            Err = 0
         End If

         ActiveControlName = Screen.ActiveControl.Name
         If Err Then
            ActiveControlName = "No Active Control"
            Err = 0
         End If

         ' Record the current active names and reset ExpiredTime if:
         '    1. They have not been recorded yet (code is running
         '       for the first time).
         '    2. The previous names are different than the current ones
         '       (the user has done something different during the timer
         '        interval).
         If (PrevControlName = "") Or (PrevFormName = "") Or (ActiveFormName <> PrevFormName) Or _  (ActiveControlName <> PrevControlName) Then
            PrevControlName = ActiveControlName
            PrevFormName = ActiveFormName
            ExpiredTime = 0
         Else
            ' ...otherwise the user was idle during the time interval, so
            ' increment the total expired time.
            ExpiredTime = ExpiredTime + Me.TimerInterval
         End If

         ' Does the total expired time exceed the IDLEMINUTES?
         ExpiredMinutes = (ExpiredTime / 1000) / 60
         If ExpiredMinutes >= IDLEMINUTES Then
            ' ...if so, then reset the expired time to zero...
            ExpiredTime = 0
            ' ...and call the IdleTimeDetected subroutine.
            IdleTimeDetected ExpiredMinutes
         End If

End Sub


This is the call sub below.   This has the message box saying no activity.  I want this message box changed into a option Yes or No.  If Yes or no isn't selected else it will close.

Sub IdleTimeDetected(ExpiredMinutes)
         Dim Msg As String
         Msg = "No user activity detected in the last "
         Msg = Msg & ExpiredMinutes & " minute(s)!"
         MsgBox Msg, 48
End SubStart Free Trial