Mac Apps Not Opening? 10 Fixes That Work

1 Check if the App Is Already Open

• Look at the Dock — a dot under the app icon means it's running
• Right-click the Dock icon → click Show All Windows
• The window may be hidden behind others or on a different Space
• Try Cmd + Tab to cycle through open apps

2 Force Quit and Relaunch

1. Press Cmd + Option + Esc to open Force Quit
2. Select the stuck app and click Force Quit
3. Wait 10 seconds, then try launching again

3 Restart Your Mac

Clears memory, flushes caches, and resets launch daemons:

1. Go to Apple Menu → Restart
2. Uncheck "Reopen windows when logging back in" for a clean restart
3. Try launching the app after restart

4 Delete the App's Preference File

Corrupted preferences are a very common cause of crashes on launch:

1. Open Finder → Go → Go to Folder (Cmd + Shift + G)
2. Type: ~/Library/Preferences/
3. Search for files with the app's name (e.g., com.apple.Safari.plist)
4. Move those files to the Trash (don't delete yet — just move)
5. Try launching the app — if it works, the old preference file was corrupt

5 Fix "App Is Damaged" / Gatekeeper Errors

If you see "the app is damaged and can't be opened" or "can't be verified":

1. Go to System Settings → Privacy & Security
2. Scroll down — if you see a button saying "Open Anyway", click it
3. Or: open Terminal and run:
   xattr -cr /Applications/AppName.app
   (replace AppName with the actual app name)
4. This strips the quarantine flag that Gatekeeper uses to block the app

6 Re-download or Reinstall the App

• App Store apps: Go to App Store → your profile → Purchased → redownload
• Third-party apps: Download a fresh copy from the developer's website
• Before reinstalling, fully delete the old version: drag to Trash, empty Trash, restart, then install fresh

7 Check Available Disk Space

1. Go to Apple Menu → System Settings → General → Storage
2. If you have less than 5GB free, many apps can't launch
3. Delete old files, empty Trash, or use Manage Storage to clear space

8 Check macOS Compatibility

• Right-click the app → Get Info → check the minimum macOS requirement
• Apps requiring macOS 12+ won't open on macOS 11 (Big Sur) or earlier
• 32-bit apps don't run on macOS Catalina (10.15) or later — no workaround exists
• Check the developer's website for a compatible version

9 Grant Required Permissions

Apps can lose permissions after macOS updates:

1. Go to System Settings → Privacy & Security
2. Check Files & Folders, Accessibility, Camera, Microphone — find the app and ensure it's allowed
3. If the app isn't listed, launch it once (even if it crashes) and check again

10 Repair Disk with First Aid

Disk errors can prevent apps from launching:

1. Open Disk Utility (Spotlight → "Disk Utility")
2. Select your main drive (Macintosh HD)
3. Click First Aid → Run
4. Repair any errors found, then restart and test the app