"Apple Cannot Check It for Malicious Software"? How to Safely Open the App on Mac

You try to open an app and macOS blocks it with a message like “[App] can’t be opened because Apple cannot check it for malicious software” or “[App] is from an unidentified developer.”

Why: This is Gatekeeper, the security feature that only lets trusted software run by default. When an app isn’t from the App Store and either isn’t notarized by Apple or comes from a developer macOS can’t verify, you’ll see this warning. The app isn’t necessarily harmful — but you should only override the block for software you actually trust.

Fix 1: Open it once with Control-click

This is the fastest way and only needs to be done once per app.

1. In Finder, find the app (usually in Applications or your Downloads folder).
2. Control-click (or right-click) the app’s icon, then choose Open from the shortcut menu.
3. In the dialog, click Open again to confirm.

The app is saved as an exception, so from now on you can open it normally by double-clicking. Using Open from the menu — instead of double-clicking — is what tells macOS you trust it.

Fix 2: Allow it from Privacy & Security settings

If double-clicking already showed the block (and the menu trick didn’t appear), approve it in System Settings instead.

1. Double-click the app once so macOS records the block.
2. Open Apple menu > System Settings > Privacy & Security.
3. Scroll down to the Security section. You’ll see a note that the app “was blocked to protect your Mac.”
4. Click Open Anyway, then authenticate with Touch ID or your password.
5. When the warning reappears, click Open.

Fix 3: Get a safer copy instead

If you can’t confirm where the app came from, the safest option is to not override the block.

• Look for the same app in the Mac App Store, where every app is reviewed by Apple.
• Or download a current, notarized version directly from the developer’s official website.
• If a download is corrupted or was modified, re-downloading a fresh copy from the official source often clears the warning on its own.

FAQ

Is the app actually dangerous? Not necessarily — the message just means macOS couldn’t automatically verify it. Only override the block for apps from a source you trust.

Where did the “Open Anyway” button go? It only appears in Privacy & Security after you’ve tried to open the blocked app at least once. Double-click the app first, then check Settings.

Can I turn Gatekeeper off entirely? Apple intentionally removed the easy “Anywhere” option because it leaves your Mac exposed. Opening individual apps as exceptions (Fix 1 or Fix 2) is the recommended, safer approach.

Sources: Apple Support — Open apps safely on your Mac · Apple Support — Open a Mac app from an unidentified developer