Hello Gemdarwen,
Thank you for your reply.
Per your previous post reply, to verify does the issue occur with the all of the following files types AVI, MPG and MP3 or only videos files recorded from the Sony HandyCam model DCR-SX40?
If the issue only occurs with video files recorded from the Sony HandyCam DCR-SX40, it appears that these videos record in a MPEG-2 format and would require that a MPEG-2 codec be installed. You may use your favorite search engine to search for MPEG-2 codec or DVD decoder that is Windows 7 compatible as Microsoft Windows operating systems provide only an MPEG-1 video decoder.
You may also view the link below provided by the device manufacturer for information regarding the MPEG-2 format.
Please also verify that the videos are in a Windows Media Player monitored folder and set the program default that you would like to use to open the video files types by going to Control Panel>Programs>Default Programs>Set your Default Programs.
For additional assistance with viewing the video file types recorded by the Sony HandyCam you may also contact the device manufacturer directly.
You may also view the links below with information regarding the supported file formats for Windows Media Player 11 and also the MPEG-2 format. This article is also applicable for Windows Media Player 12.
http://support.microsoft.com/kb/316992
http://windows.microsoft.com/en-US/windows7/Codecs-frequently-asked-questions
If the issue persists after the steps above, please post the application event logs details in its entirety by double clicking the application event log that occurred at the time of the issue and then click copy. Next, please paste the event logs details here.
Thank you,
Mary
Microsoft Answers Support Engineer
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