Microsoft has lost the latest round of its legal battle which could see it being broken up.
A Federal Appeals court has denied Microsoft's bid to delay its antitrust case.
This clears the way for the case to be sent back to a new judge to decide what penalty the company should face for breaking rules aimed at stopping it becoming too powerful.
The Supreme Court, however, still may decide whether to take up Microsoft's appeal. That decision is expected as early as October.
Microsoft had argued that US District Judge Thomas Penfield Jackson was biased, and that his interviews given to reporters tainted the case. Microsoft said the case should have been taken away from Jackson.
Judge Jackson ordered the company be split in two, but that portion of his ruling was overturned by the appeals court in June.
Microsoft said that if the appeals court didn't put the case in hold, it would put the public's faith in the judicial system in jeopardy. The appeals court unanimously disagreed.
US Court of Appeals for the District of Columbia ruled: "Microsoft has failed to demonstrate any substantial harm that would result from the reactivation of proceedings in the district court.
"It appears that Microsoft has misconstrued our opinion, particularly with respect to what would have been required to justify vacating the district court's findings of fact and conclusions of law."
The court ruled that the case should be returned to a lower court in seven days, where a new judge will be picked at random. The judge will decide how Microsoft should be penalized for its anticompetitive practices.
The penalty, which is likely to come after a hearing process, could require simple changes in Microsoft's behaviour or a breakup of the firm.
PA