Codecs for Windows Media Player
Learn tips for installing and using codecs in Windows Media Player.
Answers refer to Windows Media Player 10, unless otherwise noted.
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Why do I need a codec to play files in the Player?
Generally, Internet content providers compress the audio and video content in files or streams to make them smaller or use less bandwidth. This allows you to quickly download files or stream content. Media players, however, can't play compressed files or streams, so you need a codec (compressor/decompressor) to decompress the audio and video data so that it can be played.
For video that contains audio, you will need two different codecs installed on your computer to play back the content correctly—one codec for the video and the other codec for the audio.
Where can I get codecs for the Player?
If you have the latest version of Windows Media Player installed, the latest Windows Media audio and video codecs are included so you can play Windows Media files—Windows Media Audio (WMA) and Windows Media Video (WMV). If you have an older version of the Player, its codecs may not be up-to-date. To acquire the latest codecs, just set up the Player to download the codecs automatically by doing the following:
1. | In the Player, on the Tools tab, click Options. |
2. | On the Player tab, select the Download codecs automatically check box. |
This check box is selected by default when you install your Player. If this option is selected, but an error is displayed while a codec is being downloaded, see the next question.
When you play other types of digital media files (for example, AVI or MP3) or DVD movies, non-Microsoft codecs may be required. Because codecs are constantly being created and improved for a variety of other digital media formats, it is common to not have the necessary codec.
After you determine which codec is required, you must download the correct codec from the software provider. For more information about finding non-Microsoft codecs, see the question, "How do I find a codec?" in the Top Questions about Codecs in Windows Media Player Web page.
Keep in mind that some codecs can introduce instability with programs or with your computer in general, so make sure that a codec is from a trustworthy software provider before downloading it.
The Player displays an "error downloading codec" message. What can I do?
When you select the option that specifies that the Player download codecs automatically (see the previous question), the Player may try to download the codecs required to play the file. To ensure successful download, make sure that:
| • | You are using Windows Media Player 7 or later. |
| • | Internet Explorer 3.02 or later is installed. |
| • | The Internet security setting in Internet Explorer is set to Medium. |
| • | You are connected to the Internet while the file is playing. |
Additionally, if your computer is running Microsoft Windows NT, Windows 2000, Windows XP Professional, or Windows Server 2003, you must be logged on as an administrator or as a member of the Administrators group. If the computer is part of a network, your network administrator may prevent codecs from being downloaded to your computer. If you still get this error after you have taken all the steps to ensure a successful download, contact the network administrator for assistance.
If you still get this error, the codec server may be temporarily unavailable (in this case, try to play the file again later) or you may not be playing a Windows Media file (see the next question).
The Player displays a "missing codec" error. What can I do?
The Player has tried to automatically download the codec from the codec server, but the codec is not available. Typically, this error message is displayed if the required codec is a non-Microsoft codec. Because codecs are constantly being created and improved for a variety of digital media formats, it is common to not have the necessary codec.
For more information about finding non-Microsoft codecs, see the question, "How do I find a codec?" in the Top Questions about Codecs in Windows Media Player Web page.
Why do I get an error that says the audio codec identified by a format tag number is required to play this file?
This error message usually indicates that an audio codec on your computer is missing or damaged. To reinstall the codec, see the question, "How do I find a codec?" in the Top Questions about Codecs in Windows Media Player Web page.
Where can I learn more about codecs for the Player?
For more information, see the Top Questions about Codecs in Windows Media Player Web page.
If you don't find the answer to your question in this column, be sure to check the Archive. Media Advice is not an official Microsoft Support channel. If you need immediate help for an urgent problem, we recommend that you visit Microsoft Help and Support.