In a move to comply with a proposed antitrust settlement,


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will offer an update to Windows XP later this year that allows users to change defaults for such products as their Internet browser and email.

The so-called service pack, a general update, will let computer manufacturers and users reconfigure their PCs so that they can hide Microsoft products and set products from competitors such as


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as their defaults, said Microsoft spokesman Jim Cullinan. The products affected are email, Internet browser, media player, instant messenger and Java virtual machine.

Microsoft will offer the update, available by download to existing XP users, in beta form by the end of the month, and plans to make it publicly available by the end of the August.

Previously, computer makers could set defaults to non-Microsoft programs but could not hide Microsoft programs, except Internet Explorer. One major contention of the U.S. Justice Department's case against Microsoft was that it used its monopoly power in the operating-system market to gain an advantage against companies that make other products such as RealNetworks' multimedia player and Netscape's Internet browser.

The service pack is the first change Microsoft has made to Windows to comply with its proposed settlement with the Justice Department.

In June, the U.S. Court of Appeals found that Microsoft had illegally maintained a monopoly in computer operating systems and remanded the case to the lower court to figure out how the company should be penalized. After months of haggling, Microsoft settled the case in November with the Justice Department and half of the 18 states that were pursuing it, though that settlement is now up for federally mandated public and judicial review.

The attorneys general for nine states and the District of Columbia have called for stricter penalties against Microsoft than those in the proposed settlement. They want Microsoft to offer an alternate version of its Windows operating system without "bundled" software programs such as Windows Media, to ensure that its Office software is compatible with non-Windows systems, and to include the Java programming language in Windows XP.

Shares of Microsoft were down $1.68, or 3.1%, at $53.14 in recent trading.