"Boo Downloader is Damaged and Can't Be Opened" — How to Fix It on Mac
If macOS says "Boo Downloader is damaged and can't be opened" or blocks it as being from an unidentified developer, don't worry — the app isn't actually damaged. macOS quarantines every app downloaded from outside the App Store, and since Boo Downloader isn't yet signed with an Apple Developer certificate, Gatekeeper shows this warning by default. Here's how to open it anyway, in under a minute.
Method 1: Terminal (fastest)
- Move Boo Downloader.app to your Applications folder, if you haven't already.
- Open Terminal (search for it in Spotlight with
Cmd + Space). - Paste this command and press Enter:
xattr -cr "/Applications/Boo Downloader.app"- Open Boo Downloader from your Applications folder as normal — it will launch without the warning.
Method 2: System Settings (no Terminal)
- Try to open Boo Downloader. You'll see the warning — click Done or Cancel.
- Go to System Settings → Privacy & Security.
- Scroll down to the Security section. You'll see a message about Boo Downloader being blocked, with an Open Anyway button next to it.
- Click Open Anyway, then confirm in the popup that appears.
Why this happens
This is standard for any app distributed outside the Mac App Store that isn't yet notarized by Apple — it's not specific to Boo Downloader, and it doesn't mean the download is unsafe. It's a one-time step; once you've opened it this way, it launches normally from then on.