How to fix 0x000021a error in Windows 11 ,10

The CSRSS or Client Server Runtime Subsystem is a Windows component that is responsible for Win32 console handling operations. When this critical operation fails or is terminated in the wrong way, the system will crash into Blue Screen of Death, showing up the Error Code 0x0000021a. Starting from a bad application to corrupted system files, this error can be happening because of any reason. Follow these solutions and the CSRSS will be working again.

NOTE – 

When this error occurs, you will see that Windows is automatically booting into the Automatic Repair mode.

You should appear at this screen in Automatic Repair mode –

 

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Fix 1 –  Run the DISM revert command

Corruption in the main Windows file may cause this problem. So, try to run the DISM commands.

1. When your system boots into the Automatic Repair window, tap on the “Advanced options”.

 

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2. Now, click on the “Troubleshoot” button to proceed further.

 

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3. In the next step, tap on “Advanced options“.



 

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4. At the next step, tap on “Command Prompt“.

 

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Now, your computer will boot into the Command Prompt terminal.

6. In the next screen, select your account and tap on “Continue”  to finally get access to the terminal.

 

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7.  You have to locate which drive actually has the Windows folder. So, once the CMD appears, type this command and hit Enter.

C: 
dir

Now, you have to check whether you can find the “Windows” folder. If you can’t find it you have to look into another drive.

 

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8. Now, you have to go to another drive and look for the Windows folder.

E:
dir

Here, you can see the “Windows” folder. So, in all the upcoming commands, we will be using the “E” drive.

 

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9. So, now carefully paste-modify this command and hit Enter to start the DISM scan.

dism /image:driveletter\ /cleanup-image /revertpendingactions

[

NOTE – Replace the “driveletter” with the drive letter where you have noticed the Windows folder.

In our case, it is the “E:” drive. So, the command, in our system, will be –

dism /image:E:\ /cleanup-image /revertpendingactions

]

 

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[

OPTIONAL STEPS-After running the DISM command, there are two additional commands that you can run and check.

After opening the Command Prompt opens up, copy-paste these commands and hit Enter.

cd C:\Windows\WinSxS
move pending.xml pending.old

 

 

 

]

After this, close the Command Prompt using your mouse.

10. Now, tap on “Continue” to boot into Windows.

 

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Check if this solution works for you or not.

 

Fix 2 – Disable the driver signature enforcement

Disabling the driver signature enforcement has worked for many users.

1. When the Automatic Repair screen boots up, tap on “Advanced options“.

 

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2. Next, tap on the “Troubleshoot” to proceed further.

 

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3. In the next step, tap on “Advanced options“.

 

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4. Here, just click on “Startup Settings” to start the system in special modes.

 

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8. At the next step, tap on “Restart” to reboot.

 

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9. In the Startup Settings window, you will find 9 options.

10. Then, hit the F7 from your keyboard to select the “Disable driver signature enforcement“.

 

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This will restart the system disabling the driver signature enforcement.

Wait as your system boots up. Sign in to the system and check whether this works.

 

Fix 3 – Run CHKDSK & SFC tool

You have to run the disk checking operation and SFC tool.

1. When your system boots into the Automatic Repair window, tap on the “Advanced options”.

 

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2. Next, go this way –

Troubleshoot > Advanced options > Command Prompt

 

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In the next steps, choose your administrative account and type the account password to log in.

3. Now, you have to find which drive is containing the Windows folder.

To do that, you have to go to individual drive and perform a directory search.

C: 
dir

Here, check for the “Windows” folder. If you can’t find it you have to look into another drive for it.

 

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8. So, again go to another drive and list all the folder using these commands.

E:
dir

Here, you can see the “Windows” folder. So, in all the upcoming commands, we will be using the “E” drive.

 

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4. Once you are in Windows drive, execute this code to run a disk checking operation.

chkdsk /f /r

When you see the “Would you like to force a dismount on this volume? (Y/N)” question has appeared in the CMD terminal, type “Y” and hit Enter to start the process.

 

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5. Once it is done, run this SFC scanning command.

sfc /scannow

 

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6. After running the SFC tool, finally, copy and paste this command in the terminal and hit the Enter key from your keyboard to run the DISM command.

DISM /Online /Cleanup-Image /RestoreHealth

 

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After finishing the DISM command, close the Command Prompt. Close the Command Prompt.

7. Coming back to the first page, tap on “Continue” to start the Windows normally.

 

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This should have solved the issue you are facing.

 

Fix 4 – Uninstall any new app

If you are facing this issue just after installing a new app on your system, you have to uninstall it in the Safe Mode.

Steps to boot into the Safe Mode

1. Tap on “Advanced options” to go to the next step.

 

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2. Next, click on the “Troubleshoot” to troubleshoot this issue.



 

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3. After that, tap on the “Advanced options” to go to the next page of settings.

 

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4. In the Advanced options window, click on the “Startup Settings“.

 

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5. Now, tap on “Restart” to restart the system.

 

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This will restart your system.

6. Then, just press the F4 from your keyboard to choose the “Enable Safe Mode” option.

 

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You will see that your system is restarting automatically. In 2-3 minutes, you will be booted into your system. You will notice the desktop background is appearing to be pitch black, which is completely normal in Safe Mode.

 

Step 2 – Uninstall the app

Now, once you have booted into the system, you can easily uninstall the new faulty app from your computer.

1. Just right-tap on the Windows icon and tap on “Apps and Features“.

 

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2. When the Settings appear, scroll down through the right-hand pane to identify the app.

3. Once you have found it, tap on the three-dot menu beside it and tap on “Uninstall” to uninstall the app.

 

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Now, just complete the uninstallation process.

Once you have done that, close the Settings.

Finally, restart the system.