Windows 10: Windows defender platform stuck at version 4.18.1909.6

Hello, Windows Update fails to install some Windows Defender-related updates with error 0x80070643Aggiornamento per la piattaforma antimalware di Microsoft Defender Antivirus - KB4052623 versione 4.18.2209.7Aggiornamento per la piattaforma antimalware di Windows Defender Antivirus - KB4052623 versione 4.18.2001.10I manually downloaded the latest platform update from https://support.microsoft.com/en-us/topic/update-for-microsoft-defender-antimalware-platform-kb4052623-92e21611-8cf1-8e0e-56d6-561a07d144cc and it is successfully installed in the new path "C:\ProgramData\Microsoft\Windows

:)

 

Windows Defender platform update

Pretty common actually.

Some machines get an advance on the next platform. Which has led to some confusion as two different machines will often have different platforms. This release, 4.18-2007.8, I suspect will be pushed to everyone within the next week or so. The last one I got was 4.18.2006.10, others have gotten 4.18-2007.4 since then.

There's been some discussion in this thread of a Registry key that puts you on this advanced group getting Platforms earlier than the general public.


MS Antimalware Platform 4.18.2001.6 only on one PC

 

Windows Defender

You're not alone.

Quite a few users on Windows 7, 8.1 and 10 are reporting the same.

Microsoft has to fix it...

Doing a custom scan should still work....

Some articles (some in German, you could use
Translate or another translator to read them)...

• https://www.askwoody.com/forums/topic/ms-security-essentials-stops-scanning-after-29-files/
  

• https://www.deskmodder.de/blog/2019/09/18/windows-defender-aktuell-mit-einem-scan-problem-durch-die-antimalware-version-4-18-1908-7/
  

• https://www.borncity.com/blog/2019/09/18/scan-probleme-mit-defender-antimalware-version-4-18-1908-7/
• Microsoft tries to fix the sfc /scannow bug introduced by a patch in July, ends up clobbering Defender Malware @ AskWoody
  

 

MS Antimalware Platform 4.18.2001.6 only on one PC

Thanks!

This fits the pattern we're seeing about why some machines update their Defender platform's more frequently and often well in advance of other machines without it.

For instance under 1909, and when these registry keys were in place for me, I got 3 Platform versions in one month.

MS Antimalware Platform 4.18.2001.6 only on one PC

The question remains, what exactly triggers this registry change?

My current speculation is when a user goes looking enough times for Windows Defender Definition updates, either manually or via a custom task, such that the telemetry behavior is considered by Microsoft, much like with a CU, to be a form of user consent to be a guinea pig that's out looking for trouble, i.e. a Seeker. ;o)

Always curious about such things, I'm currently writing a scheduled task to check the Key:

Code:

to see when changes take place, hoping this evidence might shed some light on the logic.