you can click on help window anytime to get information.
You can configure the client to detect and monitor any application that runs on the client computer and that is networked. Network applications send and receive traffic. The client detects whether an application's content changes.
An application's content changes for the following reasons:
If you suspect that a Trojan horse has attacked an application, you can use network application monitoring to configure the client to block the application. You can also configure the client to ask users whether to allow or block the application.
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http://www.symantec.com/business/support/index?page=content&id=HOWTO27062