Apps Wont Open Mac

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Back up your library

If the Photos app on the Mac is open, choose Photos - Quit Photos. Hold down Option-Command and double-click the Photos icon in the Applications folder. In the Repair Library window, click Repair to rebuild your photo library. Create a new Photo library. If the Photos app on the Mac is open, choose Photos - Quit Photos. All over Microsoft apps will open without problems, but when I click to open word it just bounces as if its trying to open for a few minutes then stops bouncing. If I right click it says 'Application not responding' and will only allow me to force quit. I have updated my Mac, my Microsoft apps are all up to date and I have restarted my computer. Unless your app comes direct from the App Store, or the app’s developer got the app notarized by Apple, it won’t launch. Double click on it, and you’ll see a warning — and nothing else.

Before following any of these steps, it's a good idea to create a backup of your photo library, even if you use iCloud Photos. You can use Time Machine, use a third-party backup solution, or copy the library to an external drive. By default, your photo library is stored in the Pictures folder within your home folder.

Make sure that your software is up to date

Photos is part of the Mac operating system. You can avoid or fix many issues by running the most up-to-date version of macOS. Learn more about updating the software on your Mac.

If you use RAW images in Photos, learn more about the digital camera RAW formats supported by iOS, iPadOS, and macOS.

If you have trouble migrating an existing iPhoto or Aperture library to Photos

You might see an alert message when you first open Photos or migrate an existing iPhoto or Aperture library. Learn what to do if Photos can’t copy or create a library.

If the Media Browser isn't showing your photos and videos

Use the Media Browser to make images from your photo library available in other apps, like Pages and iMovie. The Media Browser shows only the contents of the Photos library designated as the System Photo Library. If you have more than one Photos library—and the one you're using isn't set as the System Photo Library—the Media Browser won't show its contents.

Follow these steps to designate the current library as the System Photo Library:

  1. Choose Photos > Preferences.
  2. Click the General button at the top of the Preferences window.
  3. Click Use as System Photo Library.

If you're having other issues with Photos

If you're experiencing other issues—like missing or blank photo thumbnails, unexpected behavior, or if Photos won’t open—try to see if it's an issue with your library by following these steps.

Create a new Photos library and see if your issues persist:

  1. Quit Photos.
  2. Press and hold the Option key while you open Photos.
  3. In the dialog that appears, click Create New.
  4. Give your new library a name, then click OK. Note whether Photos opens successfully with this new library.

To return to your main Photos library, quit Photos. Then open it again while holding the Option key, select your main library, and click Choose Library.

Alternatively, you can open Photos in another user account on your Mac and note whether Photos opens successfully.

Apps Won T Open Pc

If Photos opens with the new library, or in a different user account, it might mean that there's an issue with your library. Follow the steps to use the Photos library repair tool on your main Photos library.

Learn more

  • Learn how to create and order print products like books or calendars in Photos with Project Extensions.
  • Get help with iCloud Photos.

The safest place to get apps for your Mac is the App Store. Apple reviews each app in the App Store before it’s accepted and signs it to ensure that it hasn’t been tampered with or altered. If there’s ever a problem with an app, Apple can quickly remove it from the store.

If you download and install apps from the internet or directly from a developer, macOS continues to protect your Mac. When you install Mac apps, plug-ins, and installer packages from outside the App Store, macOS checks the Developer ID signature to verify that the software is from an identified developer and that it has not been altered. By default, macOS Catalina also requires software to be notarized, so you can be confident that the software you run on your Mac doesn't contain known malware. Before opening downloaded software for the first time, macOS requests your approval to make sure you aren’t misled into running software you didn’t expect.


Running software that hasn’t been signed and notarized may expose your computer and personal information to malware that can harm your Mac or compromise your privacy.

View the app security settings on your Mac

Apps Wont Open Mac

By default, the security and privacy preferences of your Mac are set to allow apps from the App Store and identified developers. For additional security, you can chose to allow only apps from the App Store.

In System Preferences, click Security & Privacy, then click General. Click the lock and enter your password to make changes. Select App Store under the header “Allow apps downloaded from.”

Open a developer-signed or notarized app

If your Mac is set to allow apps from the App Store and identified developers, the first time that you launch a new app, your Mac asks if you’re sure you want to open it.

An app that has been notarized by Apple indicates that Apple checked it for malicious software and none was detected:

Prior to macOS Catalina, opening an app that hasn't been notarized shows a yellow warning icon and asks if you're sure you want to open it:

If you see a warning message and can’t install an app

If you have set your Mac to allow apps only from the App Store and you try to install an app from elsewhere, your Mac will say that the app can't be opened because it was not downloaded from the App Store.*

If your Mac is set to allow apps from the App Store and identified developers, and you try to install an app that isn’t signed by an identified developer or—in macOS Catalina—notarized by Apple, you also see a warning that the app cannot be opened.

If you see this warning, it means that the app was not notarized, and Apple could not scan the app for known malicious software.

You may want to look for an updated version of the app in the App Store or look for an alternative app.

If macOS detects a malicious app

If macOS detects that an app has malicious content, it will notify you when you try to open it and ask you to move it to the Trash.

Mac Pro Apps Won't Open

How to open an app that hasn’t been notarized or is from an unidentified developer

Apps Won't Open Macbook Pro

Running software that hasn’t been signed and notarized may expose your computer and personal information to malware that can harm your Mac or compromise your privacy. If you’re certain that an app you want to install is from a trustworthy source and hasn’t been tampered with, you can temporarily override your Mac security settings to open it.

In macOS Catalina and macOS Mojave, when an app fails to install because it hasn’t been notarized or is from an unidentified developer, it will appear in System Preferences > Security & Privacy, under the General tab. Click Open Anyway to confirm your intent to open or install the app.

Apps Won T Open On Mac

The warning prompt reappears, and you can click Open.*

App Won't Open Macbook

The app is now saved as an exception to your security settings, and you can open it in the future by double-clicking it, just as you can any authorized app.

Application Not Responding Mac

*If you're prompted to open Finder: control-click the app in Finder, choose Open from the menu, and then click Open in the dialog that appears. Enter your admin name and password to open the app.