# Windows Defender Hacker Approved page: https://hackerapproved.com/p/windows-defender/ 12 people recommended Windows Defender in Hacker News comments, 5 had mixed feelings and 54 criticized it, November 2025 to October 2026. It was recommended in 7 of 12 months, in 12 threads. It does not meet the Hacker Approved badge rule. **Verdict:** More people criticize it than recommend it. Free built-in antivirus that runs quietly and catches most malware, though critics report false positives, slowdowns and file uploads to Microsoft. Summary written by Claude from the comments below. ## What people warn about - Slows disk and CPU use (5 comments in the sample): "a lot of the performance issues are things like crowdstrike and Defender" ([source](https://news.ycombinator.com/item?id=48589220)) "One of my greats annoyances with Windows is that Microsoft Anti-Virus will lock the file for scanning" ([source](https://news.ycombinator.com/item?id=45902968)) "top three CPU usage was and is usually from Antimalware Executable, Microsoft Defender and MS Teams" ([source](https://news.ycombinator.com/item?id=46797973)) - Uploads suspicious files to Microsoft (4 comments in the sample): "I turned sample submission off permanently via group policy after catching defender uploading places.sqlite out of my Firefox profile." ([source](https://news.ycombinator.com/item?id=48421580)) "Microsoft Defender by default could send files to their servers for inspection, and I couldn't see what was sent previously" ([source](https://news.ycombinator.com/item?id=48446538)) "I noticed that Windows Defender will upload "suspicious" files and there's no audit trail of what's being uploaded" ([source](https://news.ycombinator.com/item?id=45985681)) - Delays new binaries and git work (2 comments in the sample): "Apparently the first time a newly signed binary is run it can take up to 15 minutes for defender to allow it." ([source](https://news.ycombinator.com/item?id=46189314)) "it interfered with git in a way it couldn't detect, so I spent 2 hours diagnosing a bogus FS error" ([source](https://news.ycombinator.com/item?id=50121740)) - False positives on legitimate files (1 comment in the sample): "For may cracks Windows Defender will trip saying "Win32/Keygen" even if there's no actual malware" ([source](https://news.ycombinator.com/item?id=47722639)) ## Why people recommend it - Good enough, built into Windows (3 comments in the sample): "Microsoft fixed this with a built in virus scanner on Windows" ([source](https://news.ycombinator.com/item?id=49295108)) "Windows Defender is pretty good now" ([source](https://news.ycombinator.com/item?id=49683178)) "Microsoft Defender has solved the anti-virus problem." ([source](https://news.ycombinator.com/item?id=48957760)) - Catches malware automatically and quickly (2 comments in the sample): "Defender automatically removes malware (or more correctly, game cracks it thinks are malware) the second it hits my disk" ([source](https://news.ycombinator.com/item?id=50110372)) "Windows Defender definitions are practically real-time" ([source](https://news.ycombinator.com/item?id=50275327)) - Light and quiet to run (2 comments in the sample): "From my tests defender has minimal impact on performance even when doing a full scan" ([source](https://news.ycombinator.com/item?id=46463064)) "It’s very light and silent so I wouldn’t go out of my way to turn it off." ([source](https://news.ycombinator.com/item?id=46578230)) ## The badge A product earns the Hacker Approved badge when at least 10 people recommend it, recommenders outnumber critics at least 2 to 1 (mixed feelings count toward neither side), it was recommended in at least 4 of the 12 months and in at least 5 different threads, and no single thread supplies more than half of the people who recommend it. Health and money products are never badged. ## Cite as Hacker Approved, "Windows Defender", https://hackerapproved.com/p/windows-defender/ (12 recommend, 5 mixed, 54 criticize; Hacker News comments, November 2025 to October 2026). Counts updated 2 Nov 2026, with data through October 31, 2026.