If you've just installed an app on your Mac and see this error message:
"App.app" is damaged and can't be opened. You should move it to the Bin.
Don't worry — your app is very likely not damaged at all. The warning comes from a security feature in macOS, and it can be safely bypassed if you trust the source. Here's what's happening and how to fix it.
Why this happens
macOS includes a built-in feature called Gatekeeper that protects users from potentially malicious software. Your app may be blocked if it:
- Isn't downloaded from the Mac App Store
- Isn't signed or notarised by an Apple-verified developer
- Was downloaded through a browser such as Chrome (macOS adds a quarantine flag)
- Has been flagged as "damaged" even when it plainly isn't
This most often affects legitimate apps from smaller developers, or Chrome-based apps installed via chrome://apps.
How to fix it (step by step)
- Move the app into your Applications folder (or locate it via
chrome://appsif it's a Chrome-based app). - Double-click the app to open it.
- You'll see the error: "App.app" is damaged and can't be opened. You should move it to the Bin.
- Click Cancel — do not move it to the Bin.
- Click Cancel again if you're prompted a second time.
- Go to System Settings → Privacy & Security.
- Scroll down to the Security section.
- You should now see a message such as: "'App.app' was blocked to protect your Mac." (for example, "Grammarly.app was blocked…").
- Click Open Anyway.
- A new dialog appears repeating the "is damaged" message. This time, click Open.
- macOS may ask you to confirm your identity with Touch ID or your Mac password.
- The app will now open normally.
Optional: pin the app to your Dock for easy access in future.
A note on Chrome apps
The process is identical whether you're opening a Chrome web app from chrome://apps or a standalone app downloaded from the internet. The key is that once macOS sees your manual approval through Privacy & Security → Open Anyway, it will stop blocking that app.
If the option doesn't appear
On some Macs the "Open Anyway" button only shows for a short period after the failed launch attempt — try opening the app again, then head straight back to Privacy & Security. If you downloaded a disk image, drag the app to Applications first and run it from there rather than from the mounted DMG.
Is it safe?
If you trust the source of the app, bypassing this warning is generally safe. macOS is simply warning you that it can't verify the developer's credentials — not that the app is broken. If you're unsure where a download came from, don't bypass the warning; fetch the app again from the developer's official website.
In summary
The '"App.app" is damaged and can't be opened' error rarely means your app is genuinely damaged — it's Apple being cautious. A few clicks through Privacy & Security tells macOS "I trust this", and the app opens without issue.