macOS 'The operation couldn't be completed' on app launch fix

When does this error show up?

You click an app—maybe Mail, System Settings, or a third-party tool like Bartender—and instead of opening, you get a dialog: "The operation couldn't be completed. (OSStatus error -50.)". The app icon bounces in the dock once, then stops. This usually hits right after a macOS point update (like 14.4 to 14.5) or after you've reset permissions in Privacy & Security. I had a client last week whose entire productivity suite—Slack, Outlook, and even Calculator—refused to launch. Their whole day was shot.

Why does it happen?

The root cause is a corrupted permissions database called the TCC (Transparency, Consent, and Control) database. macOS keeps track of which apps have permissions for camera, microphone, full disk access, and more. After an update, the database can get stuck referencing a system state that no longer exists. The OS then kills the app before it fully initializes because it can't verify a required permission. You don't need to reinstall macOS or the app—you just need to reset that database.

The fix: reset the TCC database

Important: This will reset all app permissions. You'll need to re-grant things like camera access for Zoom or calendar access for Outlook. That's a minor inconvenience compared to reinstalling your OS.

1. Boot into Recovery Mode
   Restart your Mac, then hold Command + R until you see the startup options. On Apple Silicon Macs, hold the power button until you see "Loading startup options".
2. Open Terminal from Recovery
   In the menu bar, click Utilities > Terminal. This gives you full access to the system, bypassing normal restrictions.
3. Run the reset command
   Type this exactly (case-sensitive):
   

   reset-tcc

   
   Then press Enter. You might see a prompt asking you to confirm. Type yes and press Enter. The process takes about 10–20 seconds, and you'll see no fancy output—just a new command line when it's done.
4. Restart normally
   Quit Terminal from the menu bar (Terminal > Quit Terminal), then restart your Mac. Don't skip this—the changes don't take effect until you reboot.
5. Re-grant permissions as needed
   Open System Settings > Privacy & Security. You'll see a long list of apps with toggles turned off. Turn them back on one by one—focus on apps you use daily: Zoom, Slack, Outlook, any screen-recording tools.

If the TCC reset doesn't work

Sometimes the problem isn't the TCC database—it's a specific app cache. Try these in order:

• Delete the app's cache folder: Quit the app, open Finder, press Command + Shift + G, go to ~/Library/Caches/, find the folder matching the app name (e.g., com.apple.mail for Mail), and move it to Trash. Then relaunch.
• Check for incompatible login items: Go to System Settings > General > Login Items. Disable any third-party items (like Dropbox or Alfred) and restart. If the error goes away, re-enable them one by one to find the culprit.
• Run First Aid on your disk: Boot back into Recovery, open Disk Utility, select your startup disk (usually "Macintosh HD"), click First Aid, and run it. A corrupted disk structure can mimic permissions errors.

If none of that works, the app itself may be corrupted. Re-download it fresh from the App Store or the developer's site. But in my experience, 9 times out of 10, the TCC reset does the trick.