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Article ID: 915597 - Last Review: July 1, 2010 - Revision: 3.0


Microsoft works to help make computing as secure as possible for our customers. As part of this effort, Microsoft Windows Defender regularly downloads updates to the definition files that are used to identify spyware and other potentially unwanted software. Windows Defender may also periodically download detection engine updates. Microsoft delivers these updates by using Microsoft Windows Update, Automatic Updates, and Windows Server Update Service (WSUS).


For more information about Windows Defender, visit the following Web site: (
Note This is a "FAST PUBLISH" article created directly from within the Microsoft support organization. The information contained herein is provided as-is in response to emerging issues. As a result of the speed in making it available, the materials may include typographical errors and may be revised at any time without notice. See Terms of Use ( for other considerations.

  • Windows Defender
  • Microsoft Security Essentials
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