First, uninstall Windows Media Player.
START>SETTINGS>CONTROL PANEL>ADD REMOVE PROGRAMS
Remove Windows Media Player. Your current version probably is corrupted at some point.
Second, go to Windows Update site to download and install Media Player 9.
From within Internet Explorer, TOOLS> WINDOWS UPDATE. When Microsoft Windows Update page loads, scan for updates then look under the updates for Windows and find Windows Media Player. Add then install.
Third, once Media Player has been installed, open Media Player then HELP> CHECK FOR PLAYER UPDATES to download any updated codecs or other plugins.
Close Media Player and relaunch it.
Hopefully, this might correct the problem.
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