Video decoder not found when playing streaming video?
Upgrade to Windows 7. It comes with decoders for most compression types. Pre-7 users: For H264/AAC decoders install free DivX Plus codec pack. For files with AC3 audio tracks, download AC3 filter, but only use it for AC3 decoding. For MPEG2 video decoding, install Elecard decoder v2. For additional various decoders, try ffdshow at your own risk. In general, refrain from installing bundled codec packs from Internet.