The Microsoft Baseline Security Analyzer is a free utility from Microsoft that you can use to analyze your vulnerability to known security exploits in the Microsoft Windows operating environments.
This utility centrally scans Windows-based computers for common security misconfigurations and generates individual security reports for each computer that it scans.
You can download MBSA free from Microsoft at the following link: http://www.microsoft.com/technet/security/tools/mbsa2/default.mspx Supported Operating Systems: Windows 2000 Service Pack 4; Windows Server 2003; Windows Server 2008; Windows Vista; Windows XP