Fix macOS 'App is Damaged' Error
Because FluxDown is not signed with an Apple certificate, macOS may block it from opening. The steps below will help you get it running.
Last updated: 2025
Why does this happen?
macOS Gatekeeper only allows apps from the App Store or identified developers by default. FluxDown is free and open-source and does not yet hold an Apple developer certificate, so macOS shows 'damaged' or 'unidentified developer' warnings. This does not mean the app itself is harmful.
Method 1: Allow apps from Anywhere (Recommended)
- 1
Open System Settings → Privacy & Security → General and check whether the 'Anywhere' option is already enabled.
- 2
If the option is missing, open Terminal and run the command below, then press Return and enter your password:
终端sudo spctl --master-disable
- 3
After the command completes, go back to System Settings → Privacy & Security and you will see 'Anywhere' is now enabled.
Method 2: Remove the quarantine flag (if still blocked)
If enabling 'Anywhere' is not enough, use the following command to remove the quarantine attribute from the app:
sudo xattr -rd com.apple.quarantine /Applications/FluxDown.app
Replace FluxDown.app with your actual app name, or drag the app from Finder into the Terminal window after the command. Make sure there is a space after quarantine.
Method 3: Local code signing (last resort)
- 1
First install Command Line Tools:
终端xcode-select --install
- 2
Click Continue in the installer window and wait for it to finish. Then run the command below to sign the app locally:
终端sudo codesign --force --deep --sign - /Applications/FluxDown.app
Replace the app path with the actual path. You can drag the app from Finder → Applications into the Terminal window.
💡 Tip
Method 1 resolves the issue for ~85% of cases, and Method 2 covers ~90%. If none of the methods work, please let us know in our community.