Error 0x000000EF ("CRITICAL PROCESS DIED") occurs when a critical system process in Windows 11 unexpectedly stops functioning. This issue triggers a Blue Screen of Death (BSOD), causing your system to crash and possibly enter a restart loop. Causes range from corrupted system files and faulty drivers to hardware issues and malware infections.

To fix this error, start troubleshooting with the most effective methods outlined below.

Method 1: Run System File Checker (SFC) and DISM Tools

Corrupted or missing system files are a common cause of the CRITICAL PROCESS DIED error. Windows provides built-in utilities to scan and repair these files.

Step 1: Press Win + S, type cmd, right-click Command Prompt, and select "Run as administrator."

Step 2: Enter the following command and press Enter to scan and repair corrupted system files:

sfc /scannow

Wait until the scan completes. It may take several minutes. If the SFC tool reports issues it cannot fix, proceed to the next step.

Step 3: Enter the following DISM command to repair the Windows system image:

DISM /Online /Cleanup-Image /RestoreHealth

Once DISM completes, restart your computer and check if the error persists.

Method 2: Update Device Drivers

Faulty or outdated device drivers can cause critical system processes to fail. Updating your drivers helps resolve compatibility issues.

Step 1: Right-click the Start button and select "Device Manager."

Step 2: Expand each category, look for devices with a yellow exclamation mark, right-click them, and select "Update driver."

Step 3: Choose "Search automatically for drivers" and allow Windows to search and install available updates.

After updating all problematic drivers, reboot your system.

Method 3: Perform a Clean Boot

A clean boot helps identify conflicts caused by third-party software or services.

Step 1: Press Win + R, enter msconfig, and press Enter to open System Configuration.

Step 2: Under the "Services" tab, check "Hide all Microsoft services" and click "Disable all."

Step 3: Go to the "Startup" tab and click "Open Task Manager."

Step 4: Disable all startup items by selecting each and clicking "Disable at the top."

Step 5: Close Task Manager, click "OK" in System Configuration, and restart your computer. If the issue resolves, re-enable services and startup items individually to pinpoint the problematic software.

Method 4: Run Windows Memory Diagnostic

Faulty RAM modules can trigger the CRITICAL PROCESS DIED error. Test your memory using Windows Memory Diagnostic.

Step 1: Press Win + S, type "Windows Memory Diagnostic," and open the tool.

Step 2: Select "Restart now and check for problems."

Your system will restart and perform the memory check. Replace any RAM modules if errors are detected.

Method 5: Use System Restore

If the issue began after recent system changes, reverting your system to an earlier state may resolve the error. This requires you to have set up a restore point earlier.

Step 1: Press Win + S, type "Create a restore point," and open it.

Step 2: Click "System Restore," select a restore point from before the issue appeared, and follow the on-screen prompts to complete the restoration.

Your PC will restart after the restore completes.

Method 6: Reset Windows 11

If previous methods fail, resetting your system can eliminate persistent issues by reinstalling Windows.

Step 1: Press Win + I to open Settings.

Step 2: Navigate to "System" > "Recovery."

Step 3: Then click "Reset PC on the Recovery page."

Step 4: Choose "Keep my files" to retain personal data or "Remove everything" for a clean installation, then follow the prompts to complete the reset.

Your PC will restart multiple times during this process.

Method 7: Check for Malware

Malware infections can disrupt critical system processes. Run a thorough virus scan using Windows Security or a trusted antivirus program.

Step 1: Open Windows Security from the Start menu.

Step 2: Go to "Virus & threat protection" and select "Scan options."

Step 3: Choose "Full scan," and click "Scan now."

Allow the scan to complete and remove any detected threats.

After resolving the error, regularly update your system, drivers, and antivirus software to prevent future occurrences. If the problem continues despite these solutions, consider seeking professional technical support.