Users running pirated or counterfeit copies of Windows XP or Windows Server 2003 can now download Internet Explorer 7, Microsoft has announced.

From the moment it released the program almost a year ago, Microsoft has restricted the browser to users who can prove they own a legitimate copy of the operating system. Before Microsoft allows the browser to download, it runs the user's PC through a Windows Genuine Advantage (WGA) validation test, a prime part of XP's antipiracy software.

When it instituted the requirement in 2006, Microsoft said rights to IE7 were one of the rewards for being legal. But it has now changed its mind, saying the move is in users' best interest.

"Because Microsoft takes its commitment to help protect the entire Windows ecosystem seriously, we're updating the IE7 installation experience to make it available as broadly as possible to all Windows users," said Steve Reynolds, an IE program manager in a posting to a Microsoft company blog.

Microsoft has consistently touted IE7 as a more secure browser, and post-launch patch counts back that up. In the past 11 months, IE6 for Windows XP SP2 has been patched for 22 vulnerabilities, 20 of them rated critical. IE7 for XP SP2, however, has been patched only 13 times and 10 of those fixes were ranked critical.

In fact, when Microsoft announced that IE7 would not be offered to users running illegal copies of XP, some analysts questioned the company's commitment to security.

This is the first time that Microsoft has removed a WGA check for a major product. Among those that still require validation are Windows Defender, the company's antispyware software, and Windows Media Player 11.

Several people who left comments on Reynold's post wondered if there was more to the decision than meets the eye. "I am guessing that this is in reaction to Firefox's growing market share," said someone identified as Dileepa. "I am not surprised at this at all."

Mozilla’s Firefox has gained some ground on Internet Explorer since IE7's launch. According to Net Applications, a web metrics company, Firefox's share is up by about two percentage points since October 2006, while IE's total slipped by more than three points.

IE7's uptake was dramatic late last year, when it went from about a 3% share in October to 18% in December, but growth has slowed. Since April, for instance, it has increased its share by four percentage points, almost all of it at the expense of the older IE6.

Users can download IE7 from Microsoft's site immediately or wait for it to appear in Windows Update as a high priority item. It will take several months for Windows Update to roll out IE7 to all XP customers.

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