Is Microsoft Defender down?

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cojak replied

22 January 2026, 16:03
Microsoft put out a fix late last night, so it's sorted now.
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jamesbrown replied

21 January 2026, 21:30
Yeah, Alienware make gaming laptops and PCs. Seems like the issue is with a bunch of MS store apps, though, not just that one.
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Protagoras replied

21 January 2026, 20:23
I'm not a user of Microsoft operating systems, but clicked the link that jamesbrown provided out of curiosity.

I was amused to see a reference to something called "Alienware Command Center"!

At first I thought that it was a spoof, but amazingly it's a real thing.

These aliens get everywhere these days!
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jamesbrown replied

21 January 2026, 18:45
Probably this:

https://learn.microsoft.com/en-us/an...ror-0x803f8001

( Not just the reported app, but a bunch of them. )
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cojak started a topic Is Microsoft Defender down?

21 January 2026, 17:00
Is Microsoft Defender down?

The OH has been running a scan but the PC is now coming up with “Windows security not available 0x803F8001”, I’ve just opened my laptop to check, tried to open Defender and got the same error so I immediately shut it down.

Anyone else with this problem?
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