Hi escorial,

Windows Media Player does not have a DVD decoder. You need to install a DVD program such as PowerDVD, which should have come with your computer. If you do not have the disc, there is a freware player called VLC Media Player you can download which should work.

Windows XP does not include the DVD codecs.

A DVD decoder is another name for an MPEG-2 decoder. The content on DVD-Video discs is encoded in the MPEG-2 format, as is the content in DVR-MS files (Microsoft Recorded TV Shows) and some AVI files. To play these items in the Player, you need a compatible DVD decoder installed on your computer.

Plug-ins add functionality—such as audio effects or DVD capability—to Windows Media Player. You can download plug-ins for your version of the Player using the links below. Learn more.

DVD Decoder (MPEG-2 Decoder) plug-ins

Some editions of Windows include full-featured DVD playback capability in Windows Media Player. For those that don't, you can purchase a plug-in that adds features such as full-screen video playback controls and DVD chapter listings to Windows Media Player.

For Windows 7

Windows 7 Home Premium, Ultimate, and Enterprise come with DVD playback capability built in. If you're running Windows 7 Home Basic or Starter, you can upgrade your edition of Windows 7 to add full DVD capability.

For Windows XP or Windows Vista

If you're running Windows XP, Windows Vista Home Basic, Windows Vista Business, or Windows Vista Enterprise, you can enhance your DVD playback experience by purchasing one of the DVD decoder packs listed below.

For the best multimedia experience on your PC, consider upgrading to Windows 7.

CinePlayer DVD Decoder
The CinePlayer DVD Decoder delivers cinema-quality performance and superb audio clarity with support for both high-definition video and 5.1‑channel Dolby Digital audio.

• Get for Windows XP

• Get for Windows Vista

Advanced Corel DVD Decoders
Corel's Advanced DVD Decoders deliver high-definition picture clarity, vivid color, and superior sound straight to your PC. Uses WinDVD technology.

• Get for Windows XP

• Get for Windows Vista

Cyberlink PowerDVD SE
Compatible with Windows Media Player 10 and Windows Media Player 11. Plays DVDs, Dolby audio soundtracks, and TV shows recorded with Windows Media Center.

• Get for Windows XP

• Get for Windows Vista

NVIDIA DVD Decoder
Get a true home theater experience for Windows Media Player and Windows XP Media Center Edition, with DVD and MPEG-2 playback and rich surround-sound audio.

• Get for Windows XP

Audio effects (DSP) plug-ins

Add effects such as reverb, echo, and more with a DSP (digital signal processing) plug-in for Windows Media Player.

SRS Audio Enhancements
Customize your sound with patented SRS audio technologies—then enjoy 3D audio and immersive surround sound across any speaker configuration.

• Get plug-in

DFX
Enhance your listening experience with features such as 3-D surround sound, hyperbass, and headphone optimization.

• Get plug-in

If you search carefully, you can find an OEM copy of PowerDVD 9.X on eBay for around $10 including shipping. It will have the missing plug-in.

An alternative is to upgrade to WIndows 7 Home Premium (which includes a DVD codec) -- $80 on sale at Newegg today only with promo code EMCJJHE57.

PowerDVD isn't worth $10, IMHO. VLC Media Player is free and solves the problem.

PowerDVD is one of the best video players available, and for at least a year it was the only choice for high quality HD-DVD and Blu-ray playback on home theater PCs.

It's not always so simple when patented software requiring royalties is involved. VLC may be free to download but does it contain the needed MPEG-2 playback module? I just tried the Linux version and it does not.

Wikipedia: "In the case of free software such as VLC media player (which uses the ffmpeg library) and in which the software is not sold, the end-user bears the royalty."

Solved many a missing codec problem just by installing VLC. It's free to try.