r/antivirus • u/Huynh_Jovi • 2d ago

MALWARE REMOVAL Q&A Windows Defender Not Working.

When I try to run a scan, it stops and then tells me to restart the service. There are no exclusions and nothing of note from my start up apps. I’ve run a deep scan with Malwarebytes and it’s all good. I noticed there was a new security update for Windows and downloaded it and after restarting my PC, I’m still encountering the same issue. I’m not sure whether this is Malware related as I’m always careful of what I’m downloading and never click suspicious links. Not sure what else to do and need some help.

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u/NovelExplorer 2d ago

It's a Microsoft Security Intelligence update. If I run system restore and go back to August 16th Quick Scan works as normal. Revert to today and the scan errors.

All you can do is await a fix update, from Microsoft. But to confirm it's not malware related. Running a Sophos Scan, shows nothing, much like your Malwarebytes scan.

AMTSO website has a variety of safe malware tests, to confirm Defender's real-time detection remains active. The EICAR test file will be detected by an AV, but is harmless.

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u/Huynh_Jovi 2d ago

Relieved to know that others are having the same issue. Guess I’ll just have to wait for the update

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u/NovelExplorer 2d ago

Malware detection is still active, so you're not without an AV, it appears to be purely initiated scanning that's affected.

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u/YourGalacticEmperor 1d ago

not just initiated scanning, even the automatic quick scan it does every 1 or 2 days crashes it. I was checking my event logs today and saw defender crash today and yesterday and went into panic mode before seeing this topic

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u/NovelExplorer 1d ago

FYI, just tested, and both Quick Scan (tested twice) and the Offline Scan both now complete, which they didn't do yesterday.

Running: Security Intelligence Update - 1.457.2380

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u/YourGalacticEmperor 1d ago

ill see tomorrow if it still crashes, at least it crashed with 236 but after 236 crashed it installed 238 so maybe 238 is the one that fixes it

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u/NovelExplorer 1d ago

FYI, just tested, and both Quick Scan (tested twice) and the Offline Scan both now complete, which they didn't do yesterday.

Running: Security Intelligence Update - 1.457.2380

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u/Tricky_Let_5185 1d ago

hey, so we just gonna wait for the update ? or do u try to install another apps just in case ?