Just a quick note on FCS (Forefront Client Security – Microsofts antivirus solution), I was in doubt if it would be a good idea to install Windows Defender as an added security to FCS, a quick Googling revealed that;

Answer found on Technet.
Client Security cannot be used to manage Windows Defender – as a matter of fact, Client Security requires that Windows Defender be removed.

Windows Defender can be managed with a Group Policy – please see the last item here: http://www.microsoft.com/athome/security/spyware/software/about/releasenotes.mspx

–Kimborly Ditto-Ehlert

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