After a five year investigation, the European Commission announced today that Microsoft broke European Union (EU) laws “by leveraging its near monopoly in the market for PC operating systems (OS) onto the markets for work group server operating systems and for media players.”

Part of the remedy requires Microsoft to disclose iinformation that other servers need to communicate efficiently with Windows clients; the firm must do this within 120 days. The Commission also fined Microsoft € 497 million ($611.8 million) for abusing its market power.

“Dominant companies have a special responsibility to ensure that the way they do business doesn’t prevent competition on the merits and does not harm consumers and innovation ” said European Competition Commissioner Mario Monti.

a record fine, which translates to about 1 percent of cash reserves.

Microsoft is expected to appeal; it is possible that the firm could postpone the penalty for another five years.