Microsoft Releases MSBlast Mop Up Tool

Microsoft released a tool earlier this week to cleanse PCs infected with MSBlast -- the pesky worm that wriggled through thousands of computers across the globe last summer.

Company officials said they had concerns that even though systems have been patched, the worm continues to clog Internet service providers' networks.

MSBlast, which originally appeared in August, can still spread to other vulnerable PCs from patched machines which were infected prior to the patch's installation.

The free tool can be downloaded from Microsoft. The company says it removes the worm from Windows XP and Windows 2000 systems.

Many users, particularly home and small business users, may have no idea that their PCs are infected with the worm. "Those infected are still actively transmitting the worm, causing Internet congestion in the process," Microsoft said in a statement.Microsoft's MSBlast removal tool is not the first such utility. Within days of MSBlast's appearance, anti-virus firms such as Symantec had published similar tools for cleaning systems of all evidence of the worm.