另:http://stackoverflow.com/questions/3714507/c-sharp-wpf-mediaelement-not-opening-video-in-xp
这个中的:
I made sure that the latest Windows Media Player was installed on the machine (Windows Media Player 11 32-bit) and that the necessary codecs were installed, and it worked afterwards. Thanks!
大概是说:要安装最新的Media Player 版本11 & 32位 与 解码器。
如果感兴趣,你可以在不卸载最新mediaplayer 的情况下 装个xp 视频解码器 测试测试。