MPEG-4 (also known as H264) is a video codec standard used to compress video and audio data.
It’s widely used for streaming content over the internet, and Windows Media Player 11 uses H264 to compress videos.
However, some users have reported that the MPEG- 4 codec is not compatible with WMP11 on Windows 10.
- Codec errors are annoying, but the good news is that it’s easy to fix them.
- In order to fix the mpeg 4 codec error on Windows Media Player, you may need to install a third-party codec pack.
- Make sure you select the correct codec pack, as the wrong one may cause even more problems.
- Another great solution is to simply reinstall the codecs, which will instantly solve the problem.
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Check the Windows Media Format(.wma) Files
- A codec error can occur when Windows Media Format (.wma) files are corrupted.
- Try scanning the .wma file, and then try to re-play it.
- Check if the problem is resolved.
- You can also convert the .wma file to mp3 format and then play it.
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Check Windows Media Format(.wmv) Files
- Right-click on a file, then select Properties.
- Click on Details tab, then click on the Advanced button.
- Scroll down and click on the Format tab.
- Select the WMV5 (WMV9) (*.wmv) option.
- Click OK to save the settings.
Disable Hardware Acceleration
- Right-click the Windows Media Player icon and select Properties.
- Go to the Advanced tab and click on Change Settings.
- Go to the Hardware Acceleration section and uncheck the box for Use hardware acceleration when available.
- Open the Windows Media Player.
Perform a Clean Install of Windows Media Player 11
- Start by uninstalling Windows Media Player 11.
- Press Windows + R to open Run’s window.
- Input appwiz.cpl in the Open box and click OK to open the Programs and Features window.
- Select the Windows Media Player 11 entry, and click the Uninstall button.
- Press the Windows + R hotkey to open Run.
- Input appwiz.cpl in the Open box and click OK to open the Programs and Features window.
- Select the Windows Media Player 11 entry, and click the Uninstall/Change button.
- Select Next on the Setup Type window that opens.
- Select the Express Installation option in the Installation Type window.
- Press the Next button on the User Account Control window.
- Select the No option on the Do you want to allow this program to make changes to this computer window.
- Then select the Install button.
- Select the Finish option when prompted.
- Restart Windows after uninstalling the Windows Media Player 11 application. Then restart Windows after reinstalling Windows Media Player 11.
