timer 'is not declared. It may be inaccessible due to its protecti

Hi,

I'm working with an embedded vb editor in Proficy Workflow (tool of GE).
Basically it's the same as MS VB editor, (which version i don't know).

I'm getting the error, when starting my timer which I declared earlier.
I posted my question just to make sure my code is ok,

I've put the following code:

Public class Timer1
		
	public shared sub main
		Dim aTimer as New System.Timers.Timer()
	AddHandler aTimer.Elapsed, AddressOf OnTimedEvent
        ' Set the Interval to 5 seconds.
        aTimer.Interval = 5000
        aTimer.Enabled = True
	end sub
	' todo
	Private Shared Sub OnTimedEvent(ByVal source As Object, ByVal e As System.Timers.ElapsedEventArgs)
        Messagebox.show("Hello World!")
    End Sub


end class

Starting the timer:

 
Private Sub but_start_Click(ByVal sender As Object, ByVal e As System.Windows.RoutedEventArgs)
aTimer1.start()
End Sub

Where did I go wrong?

Thanks!!!