Hi ganning, after checking the issue, it seems this is a general Windows related issue. As this forum focuses on Windows SteadyState specific issues, this inquiry would best be posted to Windows forum:
http://social.technet.microsoft.com/Forums/en/category/windowsxpitpro
http://social.technet.microsoft.com/Forums/en/category/windowsvistaitpro
The reason why we recommend posting appropriately is you will get the most qualified pool of respondents, and other partners who read the forums regularly can either share their knowledge or learn from your interaction with us. Thank you for your understanding.
Also, for your information, if you are using Windows XP, you can go to Control Panel - Seucirty Center - Change the way Security Center alerts me to disable the notification.
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