Microsoft Malware Protection Center (MMPC) provides world class antimalware research and response
http://www.microsoft.com/security/portal
Who we are and what we do
The Microsoft Malware Protection Center (MMPC) provides world class antimalware research and response capabilities that support Microsoft's range of security products and services. With laboratories in multiple locations around the globe the MMPC is able to respond quickly and effectively to new malicious and potentially unwanted software threats wherever and whenever they arise.
Are you protected?
To ensure you are protected, download the latest definitions for your Microsoft security product.
Get the latest definitions
Find out how to protect your computer from malware.
I think my computer is infected – what do I do now?
What can I do to prevent my computer from becoming infected?
Additional guidance and advice
Microsoft privacy portal a target of rogue security software
Reports of rogue security programs have been more prevalent as of late. These are programs that generate misleading alerts and false detections in order to convince users to purchase illegitimate security software.
Read the full story on the blog
Microsoft Security Intelligence Report
An in-depth perspective of software vulnerabilities, malicious code threats and potentially unwanted software, focusing on trends observed during the first or second half of each year.
http://www.microsoft.com/security/portal/