Windows 10 October 18 KB5066791 & 5068164 Security Updates Causing “False Negatives”?

Stephen.S

Microsoft offered me the option to extend Windows 10 support for an additional year, which I took without hesitation. It was free after all.

After accepting the offer, I went about updating my system with the two available security updates. I believe I was advised to run Microsoft Defender alongside Bitdefender as “two is better than one”. A quick web search told me the same thing so I chose to have it run. Out of mind, out of sight.

Anyway, fast forward to today, and there was a notification from Windows Security essentially telling me all was well. I wondered why. I started looking into the Windows Security settings and found information contrary to my Bitdefender Total Security info. A check into BTS showed all was running well (Firewall, AV, etc., turned on), but MS Defender was telling me that Bitdefender was OFF, while Defender AV was ON, and, both applications' Firewall was OFF. Neither of these were true for BTS: they were both ON. (I have had no warnings from BTS.)

WHAT IS HAPPENING?! Has Microsoft gone soft(er) in the head?

AlFifi_Defender

Hi Stephen,

You’re definitely not alone! These cumulative updates (especially KB5066791 & KB5068164) seem to have introduced some quirks in how Windows Security reads third-party AV status.

I’ve also seen conflicting reports between Bitdefender Total Security and Windows Security Center — one says “all green”, the other says “we lost sight of Bitdefender”.

Personally, I trust Bitdefender’s dashboard more (the one that actually does the job) — but this smells like a false negative from the Security Center API or a race condition during service checks.

You can try this (just in case):

• Run sfc /scannow and DISM /Online /Cleanup-Image /RestoreHealth
• Restart Security Center service
• In Group Policy Editor: ensure Defender’s passive mode is enforced if Bitdefender is running

If it persists, I’d say — Microsoft didn’t just go soft… they fell asleep at the firewall. 😅

Together we shield smarter.

— AlFifi_Defender 🇸🇦

Bitdefender Community Member