Timer fires inconsistantely

I have an application that requires the use of a timer and I have created
the timer object globally:

Private t As New System.Timers.Timer(4000)

And I have a button that that triggers an event handler:


Private Sub myButton(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles Button3.Click
t.Enabled = True
AddHandler t.Elapsed, AddressOf TimerFired
End Sub

Which triggers:

Private Sub TimerFired(ByVal sender As Object, _ByVal e As
System.Timers.ElapsedEventArgs)
MsgBox(commandID)
commandID = commandID + 1

If commandID = 7 Then
t.Enabled = False
t.Stop()
t.Close()
commandID = 0
isFirstStart = False
End If
End Sub

The first the time button gets clicked, the TimerFired method fires every 4
seconds, it works great the first time, however on the second time it goes
like
Fire Fire... 4 seconds.. Fire fire... 4 seconds... fire fire

On the third time it will go like:

fire fire fire... 4 seconds fire fire fire...


How can I make it so that it will go like

fire... 4 seconds... fire... 4 seconds... fire 4 seconds etc...

each time I press the button?

p.s Please explain as simply as possible, this is my first time programming
in VB.

Thanks for any input



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