Solution to Windows Defender Error Code 0x800106ba

Windows Defender sometimes fails to work because below errors:

Error Code 0x800106ba Application failed to initialize
Error Code 0x800106ba The systems license has expired. Your logon request is denied.

The error 0x800106ba is caused by a failure in system to update Windows Defender. Result of the error is that Windows Defender fails to start and function.

To resolve the issue, you need to first uninstall and then reinstall Windows Defender on your system. The steps to do this are displayed below:

Step 1: uninstall and reinstall Windows defender.

You can either uninstall it from control panel or using windows cleanup utility to do this process.

If you decide to uninstall from control panel, follow below instructions to remove Windows Defender:

Open Start menu, select Run, type appwiz.cpl and then press Enter.
Next, from the Currently installed programs list, select Windows Defender.
Click Remove.
Follow the onscreen instructions to remove Windows Defender from your system.
Restart the PC.

After that, you will need to reinstall it back to system to protect your computer. To reinstall it, just search Windows Defender in the search engine and download it from Microsoft. Double click the setup file to finish the process.

Step 2: Re-register some relative dlls.

There are several important dlls in system32 folder that are related to Window Defender. These dlls controls how the defender works and how the system updates it. Sometimes, virus or malware may block or remove these dlls from system or registry, causing failure in starting th Windows Defender. These dlls are:

wuapi.dll
wuaueng.dll
wucltui.dll
wups.dll
wuweb.dll
atl.dll
softpub.dll
wintrust.dll
initpki.dll
mssip32.dll

To register these dlls, just open Start menu, select Run.Type the regsvr32 file_name command and then press OK.

Step 3: clear errors in system registry
Registry problems are one of the major sources for Windows Defender error 0x800106ba. This is why computer experts always recommended that users regularly scan and clean their registry with the help of a professional registry cleaner. It will fix error 0x800106ba at once.