Let me give you the logic on this.
You can use Timer Control to achieve that.
But the timer control can be set the maximum value of 65 seconds(65535 ms), you got to have a counter that gets incremented by 1 for every min(60000 ms) and finally when the counter reaches 30, you should run the code that needs to monitor mail round trip and reset its value to 0, so that it runs again when it reaches 30.
Code:
private Sub Timer1_Timer()
static nTimes as Long
If nTimes = 30 then
' Execute the code for monitor mail round trip
nTimes = 0
End If
End Sub
Set the Interval property of the Timer to 60000.
Hope that helps.
Cheers!
_________________________
-Vijay G

Strive for Perfection
