The closed-door hearings--where the decision is presented to representatives of the 15 European Union governments--will be held March 15 and 22 in Brussels, the sources said, speaking on condition of anonymity. The original dates were March 3 and 15.
The first hearing gives national regulators a last chance to raise any doubts about the European Commission's case, while the second focuses on fines and other punishments. The decision is usually adopted a day or two after the last hearing.
Commission spokeswoman Amelia Torres declined to comment.
It was not clear whether the delay was to accommodate last-minute negotiations or give the national representatives more time to review the Commission's extensive findings against the company. The draft ruling finds Microsoft abused its dominant position with Windows to gain market share in markets for media players and servers.
EU Competition Commissioner Mario Monti said Monday that he had set a date for deciding the 5-year-old case, but that a settlement was still possible.
Microsoft hopes the case can be settled, according to John Connors, the company's chief financial officer.
"We are very focused on getting things settled and having a good relationship with the (European Union)," Connors said at a Goldman Sachs investor conference in New York, according to Dow Jones Newswires. "Right now, (the EU case) is the most important case for the company, shareholders and customers.''