Ext-ms-win-oobe-query-l1-1-0.dll Missing -

Article: Fix — "ext-ms-win-oobe-query-l1-1-0.dll missing"

Method 3: Use the DISM Tool (Deployment Imaging Servicing and Management)

If SFC fails to fix the issue, the underlying component store might be damaged. DISM repairs the image Windows uses to install files.

  1. Open Terminal (Admin) as described above.
  2. Run the following command: 
    DISM /Online /Cleanup-Image /RestoreHealth
  3. This process can take up to 30 minutes. Do not close the window.
  4. Once complete, run sfc /scannow again, then restart your PC.

How to fix it

Method 6: Check for Antivirus or Third-Party Interference

Rarely, overzealous antivirus software (especially Norton, McAfee, or Avast) can quarantine or block access to legitimate API calls, causing a false "missing DLL" error. ext-ms-win-oobe-query-l1-1-0.dll missing

  1. Temporarily disable your third-party antivirus software.
  2. Try running the application again.
  3. If the error disappears, add the application and the C:\Windows\System32\ folder to your antivirus’s exclusion list.
  4. Re-enable your antivirus.

3. Use DISM (Windows 8/10/11)

If SFC doesn’t help:

DISM /Online /Cleanup-Image /RestoreHealth

Then restart and run sfc /scannow again. Article: Fix — "ext-ms-win-oobe-query-l1-1-0

6) Scan for malware

Method 4: Perform an In-Place Upgrade (Repair Install)

If the commands in Method 1 did not work, you can perform an "In-Place Upgrade." This reinstalls Windows core files but keeps all your personal files and applications intact. Open Terminal (Admin) as described above

  1. Go to the official Microsoft Windows 10 Download page (or Windows 11 page).
  2. Click Download tool now.
  3. Run the Media Creation Tool.
  4. Select Upgrade this PC now.
  5. Follow the prompts. When asked, ensure you select "Keep personal files and apps."
  6. Let the installation complete. This will rewrite the system DLL structure completely.

A Note for Developers

If you are a software developer encountering this error while compiling or running your own application, it means your application is linking to an API set that does not exist on the target system.