How to Fix "App is Damaged" Message on macOS Sierra & Later

Why Does This Error Appear?

When you try to open a downloaded Mac app, you may see a message like:

This is not because the app is actually damaged. macOS Gatekeeper blocks apps that are not code-signed by Apple or a registered developer. To resolve this, you need to disable Gatekeeper checks — either temporarily or permanently.

Quick Fix — Terminal Command

The fastest solution is to disable Gatekeeper via Terminal. Open Terminal and type:

Enter your Mac password when prompted. Now go to System Preferences → Security & Privacy → General — you will see a new option "Allow apps downloaded from: Anywhere" — select it.

Fix for a Single App (Without Disabling Gatekeeper)

If you only want to allow one specific app without disabling Gatekeeper entirely:

Replace YourApp.app with the actual name of the application. This removes the quarantine attribute from that specific app only.

Using Our Helper Tool

We provide a free Helper tool that handles all of this automatically with a simple interface. The Helper can:

• Install Xcode Command Line Tools automatically
• Disable Gatekeeper system-wide
• Enable Gatekeeper again when you are done
• Allow a single specific app to bypass Gatekeeper
• Fix damaged app errors with one click

Step-by-Step for Beginners

1. Download the app you want to run
2. Try to open it — if you see the "damaged" error, continue below
3. Open Terminal (found in Applications → Utilities)
4. Type: sudo spctl --master-disable and press Return
5. Enter your password (it will not show as you type — this is normal)
6. Open System Preferences → Security & Privacy
7. Click the padlock icon and enter your password
8. Under "Allow apps downloaded from:" select Anywhere
9. Now try opening your app again — it will work