The Fix Error Code 0xc000021a In Windows 11/10. This happens when a user-mode subsystem is hacked, like Client Server Run-Time Subsystem (CSRSS). This error also means that you can’t be sure that your system is safe. The Windows OS then goes into kernel mode and shows a blue screen. This Windows stop code 0xc000021a can show up at any time, and if it does, you will lose any work that you haven’t saved yet.
When you restore your hard drive from a backup, the system files may be damaged or missing, which can lead to this error. The 0xc000021a error can also be caused by a damaged hard drive, bad device drivers, installing software or apps that don’t work with your computer, or a Windows update that doesn’t work right.
A lot of Windows users have asked questions about stop code 0xc000021a on Reddit and the Microsoft forum. Some people said this error code showed up after installing Windows Update, while others said it showed up out of the blue while they were working on their computer. Their PC got stuck in a boot loop when they tried to restart it. Our guide will show you how to fix stop code 0xc000021a on Windows.
What is Stop Code 0xc000021a?
On Windows 10 and Windows 11, the WINLOGON_FATAL_ERROR stop code is 0xc000021a. This error happens when a routine at the user level is stopped. The system’s security is then broken, which is why the OS goes into kernel mode and shows the blue screen of death. The error message you might see could look like this:
- STOP 0xC000021A
- STATUS_SYSTEM_PROCESS_TERMINATED (Status System Process Terminated)
- HALT: c000021a {Fatal System Error}
- STOP c000021a
Why Error Code 0xc000021a In Windows 11/10
- Mismatched system files: This can happen if a system file has been corrupted or deleted, or if two different versions of the same system file are installed.
- Failed Service Pack or KB update installation: If a Service Pack or KB update installation fails, it can corrupt system files and cause this error.
- Incorrectly restored backup: If a backup program is used to restore a hard disk, but it does not correctly restore files that may have been in use, it can cause this error.
- Incompatible third-party program: If a third-party program is installed that is incompatible with Windows, it can cause this error.
Fixed: Error Code 0xc000021a In Windows 11/10
Perform startup repair
- Insert the installation media
- restart the pc
- Boot from installation media
- Choose your language
- Select “Troubleshoot”
- Select “Automatic Repair”
Run SFC scan
- Click in the search box and type “cmd”.
- Right click on cmd.exe and choose run as administrator.
- Type the command SFC/Scannow and press Enter.
- Once the process is done, restart the computer.
Update drivers
Outdated, missing or corrupt drivers are known to be one of the culprits behind this error. Therefore, updating the driver is a common solution. Especially, if you haven’t updated the driver for a long time. This process can be done manually or from a third party application.
Reset windows
- Insert the installation media
- restart the pc
- Boot from installation media
- Choose your language
- Select “Troubleshoot”
- Choose “Reset this PC”
- Choose “Completely clean disk”
system restore
- Insert the installation media
- restart the pc
- Boot from installation media
- Choose your language
- Select “Troubleshoot”
- Select “System Restore”
Check HDD health
- To open File Explorer, press the Win and E keys together.
- To get to the properties menu, right-click on the root drive, which is (C:).
- Next, click the Check button right next to “Error-checking” on the Tools tab.
- Please be patient, as this process of scanning takes some time.
- Check the report when it’s done.
FAQs
What does 0xc000021a mean as a stop code? A critical error has happened in the Windows kernel, as shown by the 0xc000021a stop code. This usually happens because of broken system files. You need to fix the broken files with a Windows 10 repair tool to fix this issue.
Most of the time, a broken user mode subsystem file is what causes the blue screen error code 0xc000021a. The following things could cause this mistake. Software or drivers that you just installed might not work with your version of Windows.
