

Say a new malware family popped up, or an older one began infecting large numbers of Windows PCs, including those still running XP. If Microsoft continued to deliver the MSRT via Windows Update, the tool would be a valuable weapon in containing infections on Windows XP PCs. Microsoft did not reply Saturday to follow-up questions asking what channels it will use to distribute the malware eraser between April 8, 2014, and July 14, 2015. Microsoft will ship its final public security patches for Windows XP in less than three months, ending nearly 13 years of support for the ultra-successful OS. But in a tacit nod to XP's widespread use, Microsoft postponed the cut-off until July 14, 2015. Originally, Microsoft had said it would stop shipping Security Essentials' signature updates to XP PCs after April 8.

The extension of MSRT's availability for Windows XP was part of Microsoft's decision last Wednesday to offer new anti-malware signatures to XP customers who run the company's free Security Essentials antivirus (AV) software.

MSRT is not an antivirus program, but rather a cleanup utility designed to eradicate malware that has already wormed onto a Windows PC. Users can also manually download the MSRT from Microsoft's website.
