Microsoft Security Essentials provides real-time protection for your home PC that guards against viruses, spyware, and other malicious software: Free, Comprehensive malware protection, Automatic updates.

Microsoft provides Internet-based services with the software.
By using these features, you consent to the transmission of this information.

• Computer Information.
• Microsoft Update Feature.
• Microsoft Digital Rights Management.
• Malicious Software Removal.
• Error Reports - Automatic.
• Potentially Unwanted Software.
  The software will search your computer for low to medium severity Malware and remove or disable it.
  It may remove or disable software which is not Potentially Unwanted Software.
• Microsoft SpyNet Participation.
• Automatic Updates.
  This software may contain Silverlight technology.
  If it does, Silverlight contains an Automatic Update feature that is on by default.

"By using the software, you accept these terms. If you do not accept them, do not use the software."
See: MS Security Essentials License Terms. Read the MS Online Privacy Statement.

Operating System:
Windows XP SP2-SP3; Vista (Gold-SP1-SP2); Win 7(+Win XP Mode)
Firefox 2.0 +; IE6+

Website: Microsoft Security Essentials

Latest definition version: 1.71.77.0
Released: Nov 21, 2009 06:30 AM UTC
Microsoft Security Essentials Version: 1.0.1611.0
Engine Version: 1.1.5302.0
Antimalware Client Version: 2.0.6212.0
https://www.microsoft.com/security/portal/D...s/HowToMSE.aspx
http://www.microsoft.com/security_essentials/