Fix NS_E_UNEXPECTED_MSAUDIO_ERROR (0XC00D0BBA) in Media Player

You're trying to play a video or audio file in Windows Media Player, and instead of music you get that error: NS_E_UNEXPECTED_MSAUDIO_ERROR (0XC00D0BBA). It's annoying, especially when the file worked fine yesterday. Let's get this fixed. I'm going to walk you through the fix that works 9 times out of 10.

The quick fix: restart the Windows Audio service

This error usually means the audio codec system got confused. The fastest way to shake it awake is to restart the Windows Audio service. Here's exactly what to do.

1. Press Windows Key + R on your keyboard. That opens the Run box.
2. Type services.msc and hit Enter. The Services window opens.
3. Scroll down until you see Windows Audio. It's near the top, usually between Windows Firewall and Windows Update.
4. Right-click Windows Audio and choose Restart. You'll see the Status column change from 'Running' to blank for a second, then back to 'Running'.
5. After it restarts, close the Services window and try playing the file again.

What you should see now: The audio or video should play without the error. If it doesn't, move to the next step.

If it still fails: clear the codec cache

Sometimes the codec cache itself is corrupt. Windows stores temporary codec data in a folder that can get gummed up. Here's how to clear it.

1. Open File Explorer. You can press Windows Key + E.
2. In the address bar, type or paste this path and press Enter:
   %windir%\ServiceProfiles\LocalService\AppData\Local\Microsoft\MediaPlayer
3. You'll see a folder named OLD inside there. If you don't see it, create a new folder named OLD in that location.
4. Select all the files inside the MediaPlayer folder (but not the OLD folder). Drag them into the OLD folder. If you get a permission warning, click Continue or Yes.
5. Close File Explorer and restart your computer.
6. After the restart, try the file again.

What you should see now: Windows Media Player rebuilds its codec cache fresh. The error should be gone.

Why this happens

The MSAudio codec is part of Media Foundation, the multimedia engine in Windows. When you play a file with certain audio formats — especially older WMA or MP3 files with weird metadata — the codec can trip over itself. It gets stuck in a loop or hits a null pointer. Restarting the service clears that stuck state. Clearing the cache removes any corrupted temporary files that keep the codec from working right.

I've seen this error most often with files recorded on older digital voice recorders or ripped from CDs with non-standard tagging. Some third-party codec packs (like K-Lite) can also cause conflicts if their MSAudio implementation isn't up to date.

Less common variations of the same error

1. The file is corrupt or incomplete

If the fix above didn't work, the file itself might be damaged. Try playing a different audio or video file. If that works, the original file is the problem. You can try repairing it, but honestly, it's often faster to re-download or re-rip it.

2. Third-party codec packs are interfering

If you have K-Lite Codec Pack, CCCP, or similar installed, they can override the built-in MSAudio codec. Sometimes their version doesn't match the Windows Media Foundation expectations. Try uninstalling the codec pack through Control Panel > Programs and Features. Then restart your PC. Windows will fall back to its own codecs.

3. Corrupted user profile

Rare, but I've seen it. If the error happens with every media file, try logging into a different Windows user account (create a test one if needed). If it works there, your main profile's Media Foundation data is toast. You can either use that new profile or rebuild your old one.

4. Missing Media Feature Pack on Windows N editions

If you're using Windows 10 or 11 N edition, it ships without media features. The MSAudio codec isn't installed. Download the Media Feature Pack from Microsoft's site. After installing, restart. This is a required piece for N editions.

Prevention tips

Once you've fixed it, here's how to keep it from coming back:

• Stick with one codec pack — if you install any, pick one reputable one like K-Lite Standard (not Mega) and keep it updated. Don't stack multiple packs.
• Keep Windows updated — Microsoft occasionally patches Media Foundation bugs. Run Windows Update monthly.
• Avoid weird metadata — if you rip CDs, use a clean ripper like Exact Audio Copy with default settings. Weird tags trip up the codec.
• Use a modern player — VLC or MPC-HC don't rely on the MSAudio codec at all. They use their own. If this error keeps happening, switching players is a permanent workaround.

That's it. The restart and cache clear fixes this 90% of the time. If you're still stuck, check the variations above. Most of the time though, you're fine after the first two steps.