What triggers this error
You'll see this error when you try to play audio or record something, and Windows throws up NS_E_NOT_CONFIGURED (0XC00D0BBC). It means the audio device you're using isn't fully set up. I see this most often on Windows 10 and 11 after a driver update or when you plug in a new microphone or speaker.
Cause #1: Wrong default audio device
This is the number one reason. Windows picks the wrong device as default. For example, you plug in a USB headset, but Windows still uses your monitor's speakers. The error shows up because that monitor doesn't have audio hardware ready to go.
Fix: Set the correct default device
- Right-click the speaker icon in the taskbar (bottom right corner).
- Select Open Sound settings.
- Under Output, look at the dropdown that says Choose your output device. Click it.
- Pick the device you want to use. If you're using speakers, pick Speakers (Realtek Audio) or whatever yours is called. If it's a headset, pick that.
- Then scroll down to Input and do the same: pick the microphone you want to use.
- After you change it, you should see the sound test button light up. Click Test next to the output device. You'll hear a tone if it works.
That's it for most people. On Windows 10, after step 2 you might see a page that says Sound Control Panel on the right. Click that, go to the Playback tab, right-click your device, and pick Set as Default Device. Then click Apply and OK.
Cause #2: Audio driver is corrupted or outdated
If the default device is set right but the error still shows up, the driver is likely messed up. This happens after a Windows update or if you install some driver update tool that breaks things.
Fix: Reinstall the audio driver
- Press Windows Key + X and pick Device Manager.
- Expand Sound, video and game controllers.
- You'll see your audio device listed, like Realtek Audio or Intel Smart Sound Technology. Right-click it and pick Uninstall device.
- A popup will ask you to confirm. Check the box that says Delete the driver software for this device. Then click Uninstall.
- Wait 10 seconds. Then restart your computer.
- After the restart, Windows will automatically find and reinstall the driver. You'll see a notification saying Installing device driver software. Let it finish.
If Windows doesn't automatically install the driver, go back to Device Manager, right-click the same spot, and pick Scan for hardware changes. It'll pick it up.
Cause #3: Audio services are stopped
Sometimes the Windows Audio service just stops running. This is less common, but I've seen it after a crash or a power outage. The error shows up because the service that manages audio devices isn't running.
Fix: Restart the Windows Audio service
- Press Windows Key + R, type
services.msc, and hit Enter. - Scroll down to Windows Audio. Right-click it and pick Restart.
- After it restarts, right-click it again and pick Properties.
- In the General tab, make sure the Startup type is set to Automatic. If it's not, change it.
- Click Apply, then OK.
Also check Windows Audio Endpoint Builder in the same list. Restart that one too. Set its startup type to Automatic.
Quick-reference summary
| Cause | What to do | Time needed |
|---|---|---|
| Wrong default device | Set the correct device in Sound settings | 2 minutes |
| Bad audio driver | Uninstall and reinstall the driver from Device Manager | 5 minutes |
| Stopped audio service | Restart Windows Audio and set to Automatic | 3 minutes |
This error is annoying but not hard to fix. Try the fixes in order. The first one works for 8 out of 10 people I help. If none of these work, you might have a hardware problem—try a different speaker or microphone to test.