Downloaded app won't open — "Apple cannot verify it is free from malware" error
You download a legit app from a developer's website, double-click it, and get a scary-sounding popup saying Apple can't verify it and refusing to open it. Clicking OK does nothing useful. The app just won't launch. It feels like your Mac is actively working against you.
Why does this happen?
macOS Gatekeeper blocks apps that aren't notarized by Apple or downloaded from the App Store. This is a real security feature — but it also blocks many legitimate apps from small developers who haven't gone through Apple's notarization process.
How to fix it
To open a blocked app: right-click (or Control+click) the app icon → Open → click Open in the dialog. This bypasses Gatekeeper for that specific app.
Or: System Settings → Privacy & Security → scroll down to see the blocked app → click Open Anyway.
Do NOT disable Gatekeeper entirely. The right-click method is safe and app-specific.
Discussion
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