Windows Media Player includes some of the most popular codecs, like MP3, Windows Media Audio, and Windows Media Video, but it doesn't include the codecs required for Blu‑ray Discs, FLAC files, or FLV files. If something isn’t working with Windows Media Player, you might not have the right codec on your PC. The easiest way to solve the problem is to go online and search for the codec you need.


  • You should only install codecs, filters, or plug-ins from trusted, authorized sources, such as the official website of the codec manufacturer. Be careful when you install codecs that you've found on the Internet, particularly the free codec packs that claim to include codecs from many companies, because these codec packs might include software that can damage your PC. If you've installed any codec packs and are having problems with the Player, we recommend that you remove them.

Here are answers to some common questions about codecs.

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What is a codec?

A codec compresses or decompresses media files such as songs or videos. Windows Media Player and other apps use codecs to play and create media files.

A codec can consist of two parts: an encoder that compresses the media file (encoding), and a decoder that decompresses the file (decoding). Some codecs include both parts, and other codecs only include one of them.

How can I find out which codecs are installed on my PC?

  1. Swipe in from the right edge of the screen, and then tap Search.
    (If you're using a mouse, point to the lower-right corner of the screen, move the mouse pointer up, and then click Search.)

  2. Enter Windows Media Player in the search box, and then tap or click Windows Media Player.

  3. On the Help menu, tap or click About Windows Media Player.

    If you can't see the Help menu, tap or click Organize, tap or click Layout, and then select Show menu bar.

  4. In the About Windows Media Player dialog box, tap or click Technical Support Information.

    Your web browser will open a page that includes a lot of detailed info about the related binary files, codecs, filters, plug-ins, and services installed on your PC. You might be able to use this info to help troubleshoot problems.

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