Dear, In IVR OD 7.0.1 , from main.flow I called a subflow. In this subflow I used Disconnect node and then return node to return to main.flow. Now in main.flow , I used another return node to close application.
in root node, i used OnDisconnect event and then connected to a Java file for EXIT process. This Java file is not called in this flow.
But if I connect to another menu in main.flow, then tihs java file is called. Not sure why? Please help.

Attached Main.flow screen.

If you have the On Disconnect item in any node whether it is in the main flow or sub flow, the disconnect event would be handled there instead of being bubbled up to the AppRoot.

Ok. So, if it is not going to Approot node, what is the purpose of using Disconnect node in flow. is this Just to inform the system?

Oh, sorry, I misunderstood you. You actually used the Disconnect node not the On Disconnect item. So the Disconnect node produce </disconnect> vxml command to disconnect the call right away but also it has the On Disconnect event handler which would handle the resulted event. You would need to throw the event back up if you want the On Disconnect in Approot to handle it.