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)
Error CausesFatal 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:
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.
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:
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.
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.
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.
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.
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
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'Error 1603: A fatal error occurred during installation.'It indicates a problem occurred during the installation process and unsuccessful installation.
Error Causes“Try that again, Something happened at our end, Waiting a bit might help, The error code is 0x80131500 in case you need it.”To fix this error, you can try changing your internet connection, toggle the date & time settings, change DNS, create a new user account, run the Microsoft Store Apps troubleshooter or reset the Microsoft Store as well re-register it using Windows PowerShell.
powershell -ExecutionPolicy Unrestricted Add-AppxPackage -DisableDevelopmentMode -Register $Env:SystemRootWinStoreAppxManifest.xml
Some users wanting to upgrade to Windows 10 from Windows 7 or Windows 8.1 experienced errors with installation. One of these errors is CPU Not Compatible. When you click and run the “Get Windows 10” from your system tray bar, you’ll receive the “CPU is not compatible with Windows 10” error. When this happens, it might be good to check if there’s a bug or if your NX feature (a requirement for the Windows 10 installation) is enabled.
Error CausesThe “CPU is not compatible with Windows 10” error normally occurs when:
To successfully upgrade to Windows 10, your CPU must support Physical Address Extension (PAE), SSE2, and NX features. If any of these features are not activated on your system, it’ll cause the CPU not compatible error. However, some users still reported experiencing this error even though their CPU has these features activated. Normally, this is due to the bug that Windows acknowledged.
If any of these two scenarios apply to your computer, the following methods will help you fix the problem:
The bug applies to some Windows 7 and Windows 8.1 systems. The bug occurs when the “Get Windows 10” app fails to recognize CPUs as being compatible. This produces a false negative result with a message, “Here’s why Windows 10 cannot be installed on this PC: The CPU isn’t supported”. To fix this bug, Microsoft released an update.
Unfortunately, the patch update (KB2976978 for Windows 8/8.1 and KB2952664 for Windows 7 SP1) to fix the bug may not be automatically downloaded to your computer. If this is the case, you need to verify first if the patch was installed correctly. To do this, follow the steps below:
A major requirement for Windows 10 upgrade is for the CPU to have Physical Address Extension (PAE), SSE2, and NX features enabled on your system. If you receive the CPU not compatible error, one possible cause is that any of the mentioned features are not available OR not enabled on your system. Here’s how you can fix this:
If changing the settings in your BIOS doesn’t do the trick, your final option is to force enable the NX bit in your Windows system. However, this is only applicable IF and ONLY IF your CPU does support it. To force enable NX bit, do the following:
SMSFromBrowser is a Browser Extension developed by MindSpark. This extension usually comes bundled up with other software or via online advertising. Allegedly this extension allows you to send SMS messages from your computer, however, all it does is point you to other websites that offer this service. While active this extension monitors your browsing behavior, it records your website visits, clicks, links, and sometimes even private information, in order to use this data to better serve additional ads. During your browsing sessions, you may encounter additional unwanted ads, sponsored links, and sometimes even pop-up ads. Several anti-virus scanners have detected this extension as a potentially unwanted extension / Browser Hijacker, and due to its privacy mining behavior, it is not recommended to keep it on your computer.
Browser hijackers (sometimes referred to as hijackware) are a kind of malicious software that modifies web browser settings without the computer owner’s knowledge or permission. These hijacks appear to be increasing at an astonishing rate around the world, and they could be actually nefarious and sometimes harmful too. Browser hijackers are capable of doing more than just modifying homepages. These are typically used to force hits to a specific site, manipulating web traffic to generate ad revenue. Though it might seem naive, these tools are made by vicious people who always try to take advantage of you, so that they can easily make money from your naive and distraction. As soon as the program attacks your laptop or computer, it starts to mess things up a whole lot that slows your system down to a crawl. In the worst-case scenario, you will be forced to deal with serious malware threats as well.
Error Causes“Windows Sandbox failed to start, Error 0x80070057, The parameter is incorrect”.This particular error in Windows Sandbox occurs due to its dependence on numerous components of Windows 10 that are related to Hyper-V and Virtualization mainly. To fix this error, there are several options you can check out. You can try to install any pending updates on your Windows 10 computer, as well as make sure that all the services related to Windows Sandbox are enabled.