To resolve this problem, configure Windows Media Player to download codecs automatically. To do this, follow these steps in Windows Media Player 11: 1. On the Tools menu, click Options. 2. Click the Player tab, click to select the Download codecs automatically check box, and then click OK. 3. Try to play the file. If you are prompted to install the codec, click Install.
If you still cannot play the file correctly, try the steps in the "Advanced troubleshooting" section. If you are not comfortable with advanced troubleshooting, you might want to ask someone for help or contact support. For information about how contact support, visit the following Microsoft Web site: http://support.microsoft.com/contactus/ (http://support.microsoft.com/contactus/)
Advanced troubleshooting
The following steps are intended for advanced computer users.

Obtain and install the codec. To do this, follow these steps in Windows Media Player 11: 1. Determine whether the codec is installed on the computer that you are using to play the file. To do this, follow these steps: 1. In the Now Playing area, right-click the file that you are trying to play, and then click Properties. 2. Click the File tab, note the codecs that are specified in the Audio codec and the Video codec areas, and then click OK. If the following conditions are true, go to step 2. * No audio codec is specified. * No video codec is specified. 3. On the Help menu, click About Windows Media Player. 4. Click the Technical Support Information hyperlink. 5. If you are trying to play an audio file, determine whether the audio codec that you noted in step 1b is listed in the Audio Codecs area. If you are trying to play a video file, determine whether the video codec or the audio codec that you noted in step 1b is listed in the Video Codecs area. If the codec is not listed, go to step 2. 6. Try to reinstall the codec. If you cannot reinstall the codec, go to step 2. 7. Try to play the file. If you can play the file, skip steps 2 and 3. 1. Install the codec. To do this, follow these steps: 1. If you receive an error message when you try to play the file, click Web Help. If you do not receive an error message when you try to play the file, go to step 3. 2. On the Microsoft Web site, click the link to the Wmplugins Web site. If this link is not present, visit the following Microsoft Web site: http://www.wmplugins.com/ItemList.aspx?typeid=8 (http://www.wmplugins.com/ItemList.aspx?typeid=8) 3. Follow the instructions on the Web site to download and install the codec for the file. If the Web site does not automatically find a codec for the file, and if either of the following conditions is true, go to step 3: * You did not note a codec in step 1b. * You cannot find the codec that you noted in step 1b on the Web site. 4. Try to play the file. If you can play the file, skip step 3. 1. Obtain the codec from a third-party vendor. For information about your hardware manufacturer, visit the following Web site: http://support.microsoft.com/gp/vendors/en-us (http://support.microsoft.com/gp/vendors/en-us)
Note If you are using Windows Media Player in an environment that is managed by a network administrator, you may have to contact the network administrator to download and install the codec.