Windows Defender DLL issue

Question

Everytime I start Defender it wont update or even start.

The error code refers me to a DLL file. I've flashed my registry back to a older registry files from 2018, I save then clean my registry once a month using CCleaner. I have not installed new programs before this happened.

Answer 1

This reminds me of an issue with a bad definition update back in March 2019

• https://techdows.com/2019/03/microsoft-security-essentials-windows-defender-0x800106ba-error.html
• https://www.askwoody.com/2019/windows-defender-security-definition-problems/
• https://answers.microsoft.com/en-us/protect/forum/all/microsoft-security-essentials-log-indicates-it/38f0cc95-d40d-4030-a1fc-36679010fcf9
• https://www.bleepingcomputer.com/news/security/microsoft-antimalware-crashing-with-error-0x800106ba-on-windows-7-and-8/

which was finally resolved by new definition updates.

Have you tried manually updating:

• https://www.microsoft.com/en-us/wdsi/definitions/antimalware-definition-release-notes

Also: https://answers.microsoft.com/en-us/protect/forum/all/problems-starting-windows-defender-in-windows/808253bb-db89-4db9-a4e5-1c91a86489e9

Answer 2

Hi Mark, 

Let me say first, that I am unfamiliar with W8.1

However, the error code does identify DLLs as the possible problem.

You should try re-registering the DLLs that are described in step 3 of the

following link.

https://support.hpe.com/hpsc/doc/public/display?docId=c01778582

I would caution you about indiscrimenitly cleaning your Registry  on a

regular basis. It buys you very little, and can cause you problems.

Beyond backing up the Registry from time to time, it is best not to fool

with it.

Regards,  Glen