Logo

How to Fix Fatal Error c000021a

Fatal Error c000021a - What is it?

Fatal Error c000021a is a type of Windows stop error also known as the blue screen of death (BSoD) error. When this error occurs, it causes the computer screen to go blue and locks the user out of the current activity.

This error code is fatal and can lead to serious issues like system crashes and freeze.

The error code is usually displayed in the following format:

STOP: c000021a {Fatal System Error}

The Windows Logon Process system process terminated unexpectedly with a status of 0xc0000034 (0x00000000 0x0000000)

Solution

Restoro box imageError Causes

Fatal Error c000021a occurs when the Windows kernel detects that either Winlogon.exe or Csrss.exe service processes have stopped responding or failed to load.  When this happens the error code pops up on the screen.

Nonetheless, this is not the only reason for the occurrence of this error. There are plenty more reasons why Fatal Error c000021a may pop on your computer screen. These include:

  • Missing or corrupt hardware drivers
  • Faulty hardware
  • Windows System Restore failed during the rollback process
  • Malware or viral infection
  • Registry issues

No matter what the reason may be, it is advisable to fix the error right away without any delays. Remember it is a fatal error and can cause a great deal of damage to your PC.

Further Information and Manual Repair

Fatal Error c000021a is a serious PC issue but this does not mean you have to hire an expert to get it fixed. The good news is that this error is actually quite easy to resolve.

You don’t have to be a technical whiz or a computer programmer to fix Fatal Error c000021a on your PC.

Here are some do it yourself methods to fix this error code right away without any hassle:

Let’s get started:

Method 1: Update Your PC Drivers

As we mentioned about corrupt or missing drivers can be one of the many reasons for the occurrence of this error. So, check the drivers first. Perform a driver scan and make sure all your drivers are updated.

Method 2: Perform a Windows System Restore

To do this, first launch Task Manager by pressing CTRL+SHIFT+ESC on your keyboard. Now click on the application tab and then click ‘New Task’ then browse.

After that, go to C:\Windows\System32\Restore  folder and then double click the rstrui.exe file. This will help start system restoration. Your computer will reboot during the process and hopefully, the error will be resolved.

Nonetheless, if the error still persists then try methods 3 and 4.

Method 3: Scan for Viruses

Sometimes Fatal Error c000021a may also occur due to malware infection. Your PC may be affected by viruses hidden in different locations without you knowing about it.

Therefore to resolve this error, it is recommended to run an antivirus and scan for viruses. If detected, remove them right away to fix the error code.

Method 4: Repair the Registry

Another method to resolve Fatal Error c000021a code on your system is to repair the registry. The registry stores all the information and activities performed on the system.

If it is not cleaned frequently, it gets loaded with too many files unnecessary and obsolete files like the junk files, cookies, internet history and temporary files which corrupts and damages the registry thereby generating blue screen of death error codes like Fatal Error c000021a.

Though you can repair the registry manually it can be both time-consuming and slightly difficult especially if you are not a computer programmer. Therefore it is advisable to download a registry cleaner to fix it right away.

Automatic Repair with Restoro.

Whether the Fatal Error c000021a code occurs due to viral infection or registry issues, download Restoro. This is a next-generation, advanced, and multi-functional PC Fixer. This software is deployed with multiple utilities such as a powerful registry cleaner, an antivirus, a system optimizer, and more.

The registry cleaner scans the entire PC and detects all types of registry issues at once. It cleans the registry, wipes out all the unnecessary files, and restores the registry back to normal.

Simultaneously, the antivirus embedded in this software detects all types of viruses including malware, adware, spyware and Trojans and removes them in seconds.

The system optimizer feature ensures the speed and performance of your PC are not compromised during the repairing process. It ensures your PC works at its optimal speed.

Restoro is a one-stop solution for all your PC needs. It has a user-friendly interface making it easy for all levels of users to work around. It is compatible with all Windows versions

Click here to download Restoro and resolve the Fatal Error c000021a code on your PC today!

Do You Need Help with Your Device?

Our Team of Experts May Help
Troubleshoot.Tech Experts are There for You!
Replace damaged files
Restore performance
Free disk space
Remove Malware
Protects WEB browser
Remove Viruses
Stop PC freezing
GET HELP
Troubleshoot.Tech experts work with all versions of Microsoft Windows including Windows 11, with Android, Mac, and more.

Share this article:

You might also like

Run Windows 10 from your USB drive
Windows 10 to goMany Linux users if not all of them can run their distros from a USB drive but did you know you can run Windows 10 from a USB drive as well? Microsoft has introduced all the way back to Windows 8 one feature called Windows To Go and it kept it in Windows 8.1 and in Windows 10 as well. This feature is intended as a convenient way for workers to carry their corporate environments with them, but having your own copy of Windows on a thumb drive could be handy for backup purposes, too, or if you frequently use public machines that lack your preferences/applications or that have a restricted OS.

What you will need?

In order to actually make Windows 10 run from a USB drive you will need the following things:
  1. USB drive with a minimum size of 20GB
  2. Working computer with Windows 10 running on it
  3. Rufus or another ISO to UBS tool, get Rufus here: https://rufus.ie/en_US/
  4. Windows 10 ISO file

Making Windows 10 UBS drive

Install Rufus on your Windows 10 and run it. Stick USB in PC and open Rufus. On the screen that follows choose your Windows 10 ISO image and under Image options choose Windows To Go. Click on ready and you are finished, that’s it. After Rufus finishes you have now fully working Windows 10 bootable drive which you can use on another PC for whatever reason.
Read More
How to Fix 0x8007043c Error Code

What is 0x8007043c Error Code?

Have you ever come across 0x8007043c error message pop up on your PC? If yes, then you should know that this error message is generated when any corresponding process or operation cannot be completed successfully by the application. This is a critical Windows OS Error message that should be fixed immediately.

Solution

Restoro box imageError Causes

The 0x8007043c error code is usually triggered by the following reasons:
  • Missing or corrupt registry files
  • Failure to update Windows Installer
  • Viruses and Spyware
Common signs of this error code are pop-up messages, program lock-ups, problems with opening documents, and screen freeze.

Further Information and Manual Repair

As soon as you experience this error on your PC, it is advisable to repair it immediately because this error poses high-security risks. Malwares and viruses are notorious for data theft. To fix the 0x8007043c error on your PC, you don’t need to take on the services of an IT professional. This error code is rated as easy to repair. By following the instruction and repair solutions given below, you can easily fix this Window error 0x8007043c in a couple of minutes by yourself. Here’s what you need to do:

Step 1: Scan for Viruses and Spyware

To stop hackers from sneaking into your PC and stealing your confidential data, you must first scan your computer for viruses and spyware on your PC. It is advisable to use a powerful antivirus to ensure your computer is totally virus and spyware clean.

Step 2: Download and Install a Registry Cleaner

After you scan for viruses, you should now download and install a registry cleaner. This is needed because an antivirus does not detect corrupt registry entries. To detect such entries, the registry cleaner tool is the best. After you download a registry cleaner on your system, click the scan button. You will have to wait for a few seconds for the scanning to finish. Once the scanning is complete, click on the ‘Repair’ button to fix the errors. After fixing all the errors, restart your computer. This is important because the registry changes will only come into effect after the system restarts. By following these 2 simple steps, you can easily resolve the 0x8007043c error on your system. However, to prevent this error from occurring again, it is recommended to run the antivirus every time you use your PC.
Read More
Create BlueTooth shortcut on desktop
If you have a BlueTooth device on your computer, you know that each time you need to receive or transfer the file you need to find the icon in the system tray, right-click on it and choose the desired option. But there is a simpler solution, create a Bluetooth icon on the desktop so it is always easy to access. Open File Explorer by pressing ⊞ WINDOWS + E Go to C:\Windows\System32 Find fsquirt.exe Right-click on it and choose copy Go to the desktop and right-click, choose paste Rename the file to Bluetooth And, you are done!
Read More
Windows Clock is missing, invisible or black
Although the Windows Updates do bring in new features and improvements, there are times when they also introduce issues as well. The main cause for these arising bugs is the incompatibility between the old and new software components. One of the issues brought in by such bugs is Clock is missing, invisible or black This problem was experienced by users after they recently installed a feature update. This particular bug can make the Windows clock in the taskbar appear to be black or invisible which makes it hard for users to read the time on their computers. According to experts, this bug has something to do with the Windows Themes and Aero styling. To fix this issue, here are some suggestions that could help but before you get started, you have to restart Explorer first and see if it can help in resolving the problem – if it didn’t, follow the options given below carefully.

Option 1 – Try to disable Custom Theme

It could be that the reason behind the black or invisible Windows Clock can be an old or an incompatible theme. You might have a custom theme in place and it became incompatible after an update. Thus, you can try switching to one of the default themes and then recreate your custom theme afterward. To do so, follow the steps below.
  • Right-click on your desktop and select Personalize.
  • Next, select Themes from the left menu and then select Windows 10 as your theme.
  • After that, you can delete all the other custom themes and create them again from scratch. This should fix the black or invisible Windows 10 Clock.

Option 2 – Try to edit your existing themes

If you don’t want to get rid of your existing themes, there is an alternative solution you can try to fix the missing Windows 10 Clock albeit it’s a bit of a complex one. Follow the given steps below to modify the existing themes and fix the missing or black Windows Clock.
  • First, you need to save your existing theme. Just simply right-click on your desktop and select Personalize and select Themes from the left menu.
  • Next, click on the Save Theme button below your custom theme to save it. You can name the theme anything.
  • After that, you can now modify the saved theme by going to C:/Users/UserName/AppData/Local/MicrosoftWindowsThemes.
  • From there, look for the file with the theme name you just saved, and then right-click on the file and open it with notepad or any other text editing app.
  • Now you have to look for the line that says, “Path=%SystemRoot%resourcesthemesAeroAeroLite.msstyles” and change it to “Path=%SystemRoot%resourcesthemesAeroAero.msstyles” and then save the file and rename it with some other name.
  • Afterward, go back to themes and select the new theme you’ve created. This should resolve the Windows Clock issue as well as other Themes and Taskbar issues.

Option 3 – Try disabling the small icons in Taskbar

This option should help you fix any Windows Clock cases. So if your Windows Clock is nowhere to be found, you can try to disable small taskbar icons on your Windows 10 PC.
  • Go to Settings > Personalization > Taskbar.
  • From there turn off the toggle button for the “Use small taskbar buttons” option. Note that this solution is only a temporary one and it may or may not work in some cases.
Read More
System Image Backup 0x807800A1 & 0x800423F3
System image backup error 0x807800A1 & 0x800423F3 appears when you are trying to create a system image backup and the operation fails to do so. If you’re faced with any of these error codes, try our recommended solutions in the order presented below and resolve the issue.

Check Volume Shadow Copy & Software Protection Services

To restart the Volume Shadow Copy Service (VSS) on Windows 10, do the following:
  • Press ⊞ Windows + X to bring up the Windows menu.
  • Click on command prompt (admin)
  • In the command prompt window, type the commands below and hit Enter after each line:
net stop vss net start vss
Once the commands execute successfully, try the system image backup again. The operation should complete successfully. You need to also check if the Software Protection Service is disabled. If it is, then Start it and ensure that it is set to default which is Automatic (Delayed Started).

Create System Image using PowerShell

Command lines are less prone to errors provided the syntax is correct, unlike GUIs that can suffer a glitch every now and then. To create a system image with PowerShell do the following:
  1. Open the Windows PowerShell as administrator. To create a System Image in Windows 10 using PowerShell, you will have to run the Wbadmin command.
  2. Inside the Powershell window type, then press Enter: wbadmin start backup-backup target: E:-include: C:-quiet-allCritical E: is the target drive where you’re going to save the system image, and C: is the system root drive where Windows is currently installed
  3. To extract the created system image, starting over from Windows 10 USB installation media, select advanced startup or open run and type: C: \ Windows \ System32 \ Shutdown.exe / r / o

Use third-party imaging software

If the previous two solutions have not managed to solve the issue there is always an option to use a third-party imaging solution. There are free open source and buying options offering various advantages each. Find out which one works best for you and use it.
Read More
Razer Hazel, an RGB mask for max protection
Razer HazelThe world today is still sadly under pandemic and by the looks of it, COVID-19 is here to stay, well at least for some time in the near future. Razer seems to think so as well since their upcoming gear is not really what you would expect. Enter Hazel, a new and upcoming Razer smart mask.

Protection

Hazel mask has a high bacterial surgical N95 filter with fluid resistance that will protect you against large droplets and splashes. A detachable active ventilator regulates airflow and is capable of filtering around 95% of airborne particles. Mask comes with a special charging case that has an auto sterilization UV light that will kill bacteria and viruses inside the case interior while it charges. When the mask is recharging it will change color from red to green visually showing the level of the current charge. Mask of course has easy to replace filters inside ventilators and Razer is standing by that fully charged mask will last enough for full-day use. An active ventilation system brings cool air while releasing breathing heat at the same time drastically reducing CO2 inside the mask that could produce dizziness and headache. Silicon guard is on its edge gluing to around your face in order to prevent exterior air sneaking inside the mask and positioning it firmly so it does not rest on your lips in order for easier and clearer communication.

Hazel personalization and technical features

Hazel has a clear and transparent design making it better for social interaction since other people will be able to see your lips and smiles thus making it more natural. A low light mode that turns on automatically when it is dark outside is also aimed for easier communication. Speaking of communication, the mask comes with voice Amp technology that has a built-in mic and amplifier thus making your voice lines clear so you are not muffled when wearing the mask itself. Your friends and other people will be able to hear you like you are not wearing a mask at all. Thicker air loops apply less pressure on ears and can be adjusted for a more secure fit, while the mask itself can be custom-made to fit your face shape. And of course Hazel comes with 16.8 million colors and a suite of effects with Razer Chroma RBG
Read More
ERR_CERT_COMMON_NAME_INVALID error in Chrome
In case you don’t know, when you visit a website that uses HTTPS, it also offers an SSL certificate to the browser in order to verify the website’s identity. Although it may contain lots of things inside it, one of them is the URL of the website. So if the certificate does not match the URL to what you entered, you will most likely get the “Server’s certificate does not match, ERR CERT COMMON NAME INVALID” error which indicates that the connection is not private and the site may try to steal your data but worry not, as this post will guide you in resolving this issue. To fix the ERR_CERT_COMMON_NAME_INVALID error, here are some suggestions that might help.

Option 1 – Check the website’s certificate

If you own the website where you’re getting the error, then you might have to check if the website’s certificate is installed properly and configured on the server as it could be the reason why you’re suddenly getting the error.

Option 2 – Check the Windows Host file

You can also try to cross-check the Windows Hosts file to find out if the website you are trying to open has been blocked, because if it is, then it’s no wonder why you’re getting the ERR_CERT_COMMON_NAME_INVALID error. There are instances when some third-party application modifies the file and adds some websites to the blocklists. So if the website is indeed blocked, you need to remove it from the list.

Option 3 – Use the Google Public DNS

You might want to change your DNS to Google Public DNS as it could also help you in fixing the ERR_CERT_COMMON_NAME_INVALID error in Chrome. To do so, follow the steps below.
  • The first thing you have to do is right-click on the network icon in the Taskbar and select Network and Sharing Center.
  • Next, click on the “Change Adapter Settings” option.
  • After that, search for the network connection that you are using to connect to the internet. Note that the option might be “Wireless Connection” or “Local Area Connection”.
  • Right-click on your network connection and click on Properties.
  • Then select the new window to choose the “Internet Protocol 4 (TCP/IPv4)” option.
  • After that, click on the Properties button and click the checkbox in the new window for the option “Use the following DNS server addresses”.
  • Type in “8.8.8.8” and “8.8.4.4” and click OK and exit.

Option 4 – Run the built-in Malware Scanner and Cleanup Tool in Chrome

In case you don’t know, there is actually a built-in malware scanner and cleanup tool in Chrome that helps you get rid of any unwanted ads, pop-ups, and even malware, as well as unusual startup pages, toolbars, and other things that could affect the performance of the browser. In addition, this built-in tool in Chrome might also help in fixing the ERR_CERT_COMMON_NAME_INVALID error.

Option 5 – Reset Chrome

Resetting Chrome can also help you get rid of the error. Resetting Chrome means restoring its default settings, disabling all the extensions, add-ons, and themes. Aside from that, the content settings will be reset as well and the cookies, cache, and site data will also be deleted. To reset Chrome, here’s what you have to do:
  • Open Google Chrome, then tap the Alt + F keys.
  • After that, click on Settings.
  • Next, scroll down until you see the Advanced option, once you see it, click on it.
  • After clicking the Advanced option, go to the “Restore and clean up option and click on the “Restore settings to their original defaults” option to reset Google Chrome.
  • Now restart Google Chrome.
Read More
What to do if Windows 10 Disk Management is not working
The Disk Management tool in Windows 10 is a built-in tool that contains a user interface used to manage disk partitions to administrators of the computer. There are lots of instances when you have to change the size of the hard disk partition or reduce the size and so on. This is where the Disk Management tool comes in. It’s useful as the command line interface can be quite confusing and risky for some users. However, there are cases when this tool stops working. A proof of this the reports submitted recently by some Windows 10 users. Based on the reports, the Disk Management does not load or respond. If you are having the same problem, read on as this post will give you some suggestions on what you can do to resolve the problem.

Option 1 – Try restarting the Disk Management Service

  • Tap the Win + R key combination to open the Run dialog box.
  • Then type “services.msc” in the field and hit Enter or click OK to open the Windows Services Manager.
  • Next, scroll down in the service list until you see the Virtual Disk Service. Double click on it to open and then select Automatic.
  • Click on Apply and OK to save the changes made.
  • If it hasn’t started yet, you can just click on the Start button to start the Service. The Virtual Disk service provides management services for disk, volumes, file systems as well as storage arrays.
  • Now save all the changes you’ve made and restart your computer. Then check if you can now use the Disk Management tool without any problem.

Option 2 – Try using the System File Checker scan

System File Checker or SFC is a built-in command utility that helps in restoring corrupted files as well as missing files. It replaces bad and corrupted system files with good system files that might be causing some issues with the Disk Management tool. To run the SFC command, follow the steps given below.
  • Boot your PC into Safe Mode.
  • Tap Win + R to launch Run.
  • Type in cmd in the field and tap Enter.
  • After opening Command Prompt, type in sfc /scannow
The command will start a system scan which will take a few whiles before it finishes. Once it’s done, you could get the following results:
  1. Windows Resource Protection did not find any integrity violations.
  2. Windows Resource Protection found corrupt files and successfully repaired them.
  3. Windows Resource Protection found corrupt files but was unable to fix some of them.

Option 3 – Try using the DISM tool

Aside from the System File Checker, the DISM tool can also help you resolve the issue with the Disk Management tool. It helps in restoring the health of your computer.
  • Open the Command Prompt as admin.
  • Then type in this command: Dism /Online /Cleanup-Image /RestoreHealth
  • Do not close the window if the process takes a while as it will probably take a few minutes to finish.

Option 4 – Try using Diskpart and Fsutil

If both the System File Checker and DISM tool didn’t work, you can use command-line tools like diskpart and fsutil. These command-line tools are powerful but you need to be careful especially if you’re not that familiar with using them. However, it’s recommended that you have somebody who knows if you’re really inexperienced with this kind of stuff.
Read More
Fix Network driver issue in Windows
The network driver error is a not serious Windows issue.  It happens from time to time and luckily it can be solved with a little effort and in a short time period. Today in this article we will explore the most common solutions for driver malfunction for Network adapter inside Windows 10. If you have this particular problem, go from step 1 to the last step since all steps are meant to go from simplest to the most complex. All of that being said let us fix your Network driver issue.
  1. Check to see if the cable is plugged in and not malfunctioned

    The first common issue of the network now working can be cable malfunction or bad contact in your network adapter or in HUB/SWITCH. There are various tools to check the quality and working order of cable but you could also make sure that it is not a cable issue by trying connection with the correct working cable. If the network is restored with another cable then change the malfunctioning cable and your issue is resolved if the problem persists move to the next step.
  2. Check if Windows troubleshooter will resolve the issue

    Righ-click on the network icon in the taskbar and choose to troubleshoot problems. Windows built-in tools could resolve issues and fix them for you. If by any chance Windows is not able to find or resolve issues move to the next step.
  3. Check if the Device Manager is reporting an error and update the driver

    If the hardware is functioning properly then the issue might be in Windows not detecting device or driver malfunction. In any case, the Device Manager will be the one who will report this problem. In order to check to see if the driver is properly working press ⊞ WINDOWS + X to open the hidden start menu. keyboard with windows and x marked Once it opens, click on Device Manager to open it, If you have a driver device error inside Windows, you should see it immediately when entering the Device Manager, it will have a yellow exclamation mark beside it. Right-click on it and choose update driver.
  4. Reinstall driver

    If driver update failed or you already have the latest drivers, reinstalling them could fix the issue since drivers might have corrupted during installation of some update or application. Follow steps from point 3 to get to the driver in Device Manager, then right-click on it but instead of update choose to uninstall. Reboot Windows once the driver is uninstalled and Windows will install a new one automatically. If you do not want to update drivers automatically, do not restart your system, instead install the latest driver for your device, then reboot. Since this is a network error, you will have to get drivers on another computer and transfer them via USB to malfunctioning one.
  5. Check Windows update

    Check to see if the latest Windows update is installed, update your Windows if needed
  6. Fix driver issue with DRIVERFIX

    If everything else fails, get DRIVERFIX, a premium solution for your PC issues, and fix driver errors.
Read More
Fix Generic PnP monitor driver issue
Universal PnP or plug-and-play monitors use a generic PnP Windows driver. Whenever a user plugs a USB device or monitor into a PC the system will automatically identify the device and it will install the proper driver for smooth running. Generic PnP Monitor in Windows 10 means that Windows 10 installed a monitor driver as the PNP did not recognize the device. This generic PnP monitor driver may not work perfectly like the manufacturer’s one. It can lead to issues like unable to set the best monitor resolution and the screen refresh rate. Therefore, it is important to fix this issue. All of that being said let us fix your PnP display driver issue.
  1. Reconnect monitor

    Always try this first, just by unplugging the monitor and then plugging it back may resolve the issue, if the monitor was not detected properly the first time, there are very high chances that this method will resolve the issue.
  2. Check if the Device Manager is reporting an error and update the driver

    If the hardware is functioning properly then the issue might be in Windows not detecting device or driver malfunction. In any case, the Device Manager will be the one who will report this problem. In order to check to see if the driver is properly working press ⊞ WINDOWS + X to open the hidden start menu. keyboard with windows and x marked Once it opens, click on Device Manager to open it, If you have a driver device error inside Windows, you should see it immediately when entering the Device Manager, it will have a yellow exclamation mark beside it. Right-click on it and choose update driver.
  3. Reinstall driver

    If driver update failed or you already have the latest drivers, reinstalling them could fix the issue since drivers might have corrupted during installation of some update or application. Follow steps from point 3 to get to the driver in Device Manager, then right-click on it but instead of update choose to uninstall. Reboot Windows once the driver is uninstalled and Windows will install a new one automatically. If you do not want to update drivers automatically install the latest driver for your device, then reboot.
  4. Check Windows update

    Check to see if the latest Windows update is installed, update your Windows if needed
  5. Fix driver issue with DRIVERFIX

    If everything else fails, get DRIVERFIX, a premium solution for your PC issues, and fix driver errors.
Read More
1 2 3 171
Logo
Copyright © 2023, ErrorTools. All Rights Reserved
Trademark: Microsoft Windows logos are registered trademarks of Microsoft. Disclaimer: ErrorTools.com is not affiliated with Microsoft, nor claims direct affiliation.
The information on this page is provided for information purposes only.
DMCA.com Protection Status