BEIJING, June 20 (Xinhuanet) -- A 49-page anti-trust complaint by Google Inc. has forced Microsoft Corp. to make changes to the program that helps Windows Vista users search their hard drives, according to a U.S. Justice Department report Tuesday.

    Google filed the complaint with the Justice Department in April claiming Vista's desktop search tool slowed down competing programs, including Google's own free offering, and it's difficult for users to understand how to turn off the Microsoft program.

    Initially, Microsoft dismissed the allegations, saying regulators had reviewed the program before Vista launched. However, Brad Smith, Microsoft's general counsel, said in an interview last week the company was willing to make changes if necessary.

    In response to claims that Vista's "Instant Search" slows competing products, Microsoft agreed to give competitors technical information to help optimize performance.

    Microsoft said it expects these changes to be available with its first service pack for Vista. The software maker plans to release an early version of Service Pack 1 by the end of the year.

    Google's claims were intended to show that the world's largest software maker is not complying with a settlement reached in 2002 after the government concluded Microsoft used its near-ubiquitous Windows operating system to throttle competition. As part of the settlement, Microsoft is bound by a consent decree that requires it to help rivals build software that runs smoothly on Windows.

    Google's complaint came just a few days after Microsoft called for antitrust regulators to scrutinize the search company's planned 3.1 billion U.S. dollar acquisition of online ad service DoubleClick Inc.

    These recent moves are part of a broader battle between the two. While Windows continues to dominate the desktop operating system market, Google's ability to make money from search advertising has left Microsoft scrambling to catch up. Google has also stepped into traditional Microsoft territory in the past year with a set of free, Web-based programs for word processing, spreadsheets and presentations.

    (Agencies)