A new demo has been added in the Windows Windows XP Professional demo portion.The detail of this demo is

Title: How to Configure Data Execution Prevention (DEP) in Windows XP

Objective: The objective of this demo is to teach you how to configure Data Execution Prevention in Windows XP. Data Execution Prevention (DEP) helps prevent damage from viruses and other security threats that attack by running (executing) malicious code from memory locations that only Windows and other programs should use. To use DEP, your computer must be running Microsoft Windows XP Service Pack 2 (SP2) or later. DEP does not help prevent harmful programs from being installed on your computer. Instead, it monitors your programs to determine if they use system memory safely. To do this, DEP software works alone or with compatible microprocessors to mark some memory locations as "non-executable". If a program tries to run code—malicious or not—from a protected location, DEP closes the program and notifies you.

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