Show pageOld revisionsBacklinksBack to top This page is read only. You can view the source, but not change it. Ask your administrator if you think this is wrong. ===== OnAirScreen: Make OnAirScreen Application executable under macOS ===== <WRAP round tip 60%> When you download **OnAirScreen** as a `.dmg` from the internet (AstraStudio Customer Portal, our online shop), macOS marks the app with a **quarantine flag**. Gatekeeper then blocks the app on first launch — often with a message like *"OnAirScreen can't be opened because Apple cannot check it for malicious software"* or *"the developer cannot be verified"*. </WRAP> OnAirScreen is **not signed with an Apple Developer ID certificate**, so macOS treats every downloaded copy as untrusted until you explicitly allow it. ==== Why is this necessary? ==== * **Gatekeeper** checks apps before they run. * Downloaded files get the extended attribute ''com.apple.quarantine''. * Without a trusted signature, macOS refuses to start the app. * Removing the quarantine flag tells macOS you trust this copy. This is normal for unsigned open-source macOS apps — not a sign that OnAirScreen is broken. ==== Remove the quarantine flag ==== **Option A — Terminal (recommended)** Open **Terminal** (''Applications → Utilities → Terminal'') and run: <code bash> sudo xattr -d com.apple.quarantine /Applications/OnAirScreen.app </code> Enter your Mac password (nothing appears while typing — that is normal). Then start OnAirScreen from **Applications** or Launchpad. **Option B — Finder (without Terminal)** - Drag **OnAirScreen.app** from the DMG to **Applications** - Right-click (or Control-click) **OnAirScreen.app** → **Open** - In the dialog, click **Open** again to confirm - macOS remembers this choice for future launches ==== Verify (optional) ==== Check whether the quarantine flag is still set: <code bash> xattr -l /Applications/OnAirScreen.app </code> If removal worked, ''com.apple.quarantine'' should **not** appear in the output. ==== Troubleshooting ==== **"No such xattr: com.apple.quarantine"** The flag is already removed — try launching the app normally. **"Operation not permitted"** * Confirm the path: ''/Applications/OnAirScreen.app'' * Use ''sudo'' as shown above * On corporate Macs, admin rights or MDM policies may block this **App still won't start** * ''System Settings → Privacy & Security'' — look for **Open Anyway** * Ensure you copied the app to **Applications**, not running it directly from the DMG <WRAP round tip 60%> Only remove the quarantine flag for OnAirScreen copies you obtained from a **trusted source** (official website or your own CI build). </WRAP> onairscreen_macos.txt Last modified: 06.07.2026 20:09by admin