In Windows 7, Media Player started using Windows Media Foundation modules to play MPEG2 Transport files and files with certain extensions (.mp4, .3g2, .3gp, .3gp2, .3gpp, .m4a, .m4v, .mov, .mp4v). These Windows Media Foundation modules are not provided by LEAD and do not handle all the file formats properly. As a result, certain files display incorrectly in Media Player but work correctly in the LEADTOOLS demos.
LEAD has created a utility (ltmmWin7PlaybackUtil.exe), which allows you to change the Media Player behavior on this computer to specify that it use DirectShow (and therefore LEAD modules) to play one or more of the above file formats. It is up to you whether you want to disable Windows Media foundation support for all file formats or only for the formats being displayed incorrectly by Windows Media Player.