How to Fix Windows 10 Error Code 0x80070426

The Microsoft Windows Defender program is a default security application instead of Microsoft Security Essentials which was previously available. Now, Windows 10 system comes preloaded with Windows Defender and the real-time protection is activated too. But if in case, you’ve previously used Windows 7/8.1 and now you’ve just upgraded to Windows 10 OS build, the Windows Defender will take place over the Security Essentials program. But plenty of users have started reporting that somehow after updating to Windows 10, they’re receiving an Error Code 0x80070426. If you’re one of them, follow this guide.

After upgrading to Windows 10 OS build, something goes wrong and Windows Defender simply gets failed to take over the Microsoft Security Essentials. This basically results to have both the Defender and Security Essentials programs installed on Windows 10 which starts causing multiple troubles. As Windows 10 doesn’t work with Security Essentials and Defender can’t run properly, your system doesn’t have any kind of security protection. It’s very risky and vulnerable to unwanted malware attacks, spyware, or virus affection as well.

So, whenever affected users trying to turn on the disabled Defender program, the Microsoft Security Client dialog appears that “An error has occurred in program initialization. If this problem continues, contact your System Administrator. Error Code: 0x80070426.” Well, if you’re also encountering the same error message, follow the possible workarounds below that should work for you.

1. Stop Windows Defender Service

Make sure to stop the Windows Defender service first and then you can be able to uninstall the Microsoft Security Essentials program completely. To do so:

Press Windows + R keys to open up a Run dialog box.
Type taskmgr and hit Enter > Scroll down and locate Windows Defender Service (WinDefend) from the list.
Right-click on it and select Stop.
Now, the Windows system will stop the service. Simply, go to Control Panel from the Start Menu > Choose to Uninstall a Program.
Right-click on the Microsoft Security Essentials program and click on Uninstall.
Once done, restart your computer to apply changes.
Finally, you can press Windows + I keys to open Windows Settings.
Select Update & Security > Click on Windows Defender.

Make sure that Real-time protection is turned on.
Enjoy!

However, if this method doesn’t help you out, you can follow the next method.

2. Run SFC

It’s most likely that the Windows 10 Error Code 0x80070426 occurs due to some issues with the Windows system files. If you’re feeling so, we’ll recommend you to perform an SFC scan. To perform it:

Click on the Start Menu > Type cmd > Right-click on Command Prompt from the search result.
Select Run as administrator > If prompted by UAC, click on Yes to proceed.
Once the command prompt window is opened, you can copy & paste the following command:

dism.exe /online /cleanup-image /restorehealth

After completing the process, you can type the below command, and hit Enter to execute it:

sfc /scannow

The scan will take some time. Once done, restart your PC/Laptop to apply changes.

3. Disable All Services

However, if the problem is still bothering you a lot, you should Hide Microsoft services and disable all services to check whether the problem has been fixed or not. To do this:

Press Windows + R keys to open up a Run dialog box.

Type msconfig and hit Enter to open System Configuration.
Go to Services > Click on Hide all Microsoft services to enable it.

Now, click on Disable all > Select OK.
Once done, go to Startup > Click on Open Task Manager.

Go to Startup > Click to select already enabled services (High or Medium Impact).
Disable the services one by one according to your preference.
Finally, close Task Manager > Close System Configuration.
Restart your computer to change effects.

4. Run Windows Update Troubleshooter

Still, the Windows 10 Error Code 0x80070426 is appearing to you? Well, you should run the Windows Update Troubleshooter scan to check whether any kind of Windows update-related issue is causing such an error or not. Sometimes it can possible that any missing or corrupted or pending software update installation file may start bothering you. To do this:

Press Windows + I keys to open up Windows Settings.
Click on Troubleshoot from the left pane.
Now, click on Additional troubleshooter from the right pane.

Click on Windows Update and select Run the troubleshooter.
Follow the on-screen prompts to complete the process.
Once done, restart your computer to apply changes.

5. Reset Windows Update Components

If none of the methods worked for you, try resetting the Windows Update Components on your PC/Laptop to remove any kinds of corrupted or missing files. To do that:

Click on the Start Menu > Type cmd > Right-click on Command Prompt from the search result.
Select Run as administrator > If prompted by UAC, click on Yes to proceed.
Once the Command Prompt window opens, type and hit Enter to execute the following commands one by one:

net stop bits

net stop wuauserv

net stop appidsvc

net stop cryptsvc

Again you’ll need to input the following commands and hit Enter to execute:

ren %systemroot%\softwaredistribution softwaredistribution.old

ren %systemroot%\system32\catroot2 catroot2.old

You’ll need to restart the services that you’ve already disabled. So, input the following commands and hit Enter to execute them:

net start bits

net start wuauserv

net start appidsvc

net start cryptsvc

Make sure to press Windows + I keys to open Windows Settings > Update & Security > Check for Windows Updates. If there is an update available, download and install it.
Finally, restart your computer, and check for the error again.

That’s it, guys. We hope you’ve found this guide useful. For additional queries, you can comment below.

How to Fix Windows 10 Error Code 0x80070426