If Security Intelligence Updates for Microsoft Defender Antivirus is not downloading or installing automatically on Windows 11/10, use the solutions in this post.

General Users: For users who do not engage in high-risk activities like visiting sketchy websites or downloading from untrusted sources, Windows Defender may be sufficient.

AV-TEST, which tests and ranks antivirus solutions, has conducted its first Windows 11-based security test. However, Defender, despite all of Microsoft's touting, has managed to come in last place.

Microsoft has confirmed it has fixed the Local Security Authority (LSA) is off issue with a recent update to Defender. The company is also pushing out new kernel-mode hardware stack protection.

A new wave of attacks by the DarkGate malware operation exploits a now-fixed Windows Defender SmartScreen vulnerability to bypass security checks and automatically install fake software installers.

Why it matters: Microsoft has released a crucial bug-fixing update to its Windows Defender antimalware application. Its arrival means that some unlucky Firefox users should now get a much smoother ...

If the scan of your hard drive with Microsoft Defender seems to take forever, it's worth finding out why.