One of the nine US states that took Microsoft to court is to appeal against the federal court ruling upholding the software giant's antitrust deal.
According to The Seattle Times the Massachusetts attorney general, Thomas Reilly, said US District Judge Colleen Kollar-Kotelly had done little more than "accept Microsoft's loophole-riddled deal" in her ruling.
The appeal is necessary to protect consumers, he added.
But legal experts say it could take years to resolve an appeal, and that the chances of success for Massachusetts are slim.
The seven other states involved in the court case, and the District of Columbia, said they would not appeal the decision. West Virginia is expected to announce its intention this week.
Microsoft said it would focus on complying with Kollar-Kotelly's ruling.
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