Update Issued for Microsoft’s Windows XP

Microsoft Corp. on Friday completed a long-awaited update to Windows XP that fixes many of the security holes exploited by hackers to attack computers running the ubiquitous operating system.

The free Service Pack 2, which can be downloaded or ordered on a CD, was the work of thousands of Microsoft engineers who labored since late last year to shore up Windows XP against the sort of viruses, worms and trojans that cripple millions of computers annually.

Although Service Pack 2 brings Microsoft virtually no revenue, it may help restore credibility to the world’s biggest software maker’s claim that it takes security seriously. Microsoft admitted last year that a rash of Internet attacks had cost it sales.

Rival operating system Linux, meanwhile, has gained market share in part because corporate technology buyers believe it is less vulnerable to viruses and hacking.

“If they don’t get this perception turned around that Windows is not secure, it will in the long run cost them business,” said analyst Michael Cherry of Directions on Microsoft, a research group that monitors the Redmond, Wash.-based company. “They did a good job with this.”

Security experts said the spread of recent viruses such as MyDoom and Blaster would have been drastically curtailed if all the security features in Service Pack 2 had been installed worldwide. The program includes a collection of various patches that have been available for months as well as new features designed for the next version of Windows, code-named Longhorn.

Microsoft has long employed service packs to update its operating systems between full releases. Windows XP is three years old. Experts said Service Pack 2 was one of the largest and most comprehensive updates, requiring about 80 megabytes of data.

In the next two months, Microsoft expects to distribute the improvements to the 100 million Windows XP computers that are set to receive online updates automatically. The company urged the other roughly 100 million Windows XP users who don’t use the update feature to change their settings so they can receive it.

After Aug. 25, customers can order the service pack on a free CD from Microsoft’s website (www.microsoft.com), a route preferable for those with slow dial-up Internet connections. New PCs will come with the upgrade installed starting this fall.

The most significant change to Windows XP is an enhanced firewall, which blocks information from entering or leaving a machine.

The program also fixes holes in Microsoft’s Web browser and tells users whether their firewall and antivirus software are running and up to date.

A minority of other companies’ programs may not work on top of the updated operating system, though Microsoft said it had tested thousands of such applications for compatibility. Some Internet-based games and other products will require users to change the settings on the firewall.

Overall, the new features should make computing somewhat less hazardous, said Brent Lymer, senior director of product and partner management at McAfee Inc. of Santa Clara, Calif., one of the major makers of firewalls and antivirus programs. It will make hackers work harder to find new bugs to exploit.

“Service Pack 2 makes it safer today, but the benchmarks keep shifting,” Lymer said. “It will be an interesting time over the next few months.”

Microsoft shares fell 39 cents to $27.14 on Nasdaq.