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Cannot Install CPT in Mac OS 10.15 Catalina or Later

Classroom Presentation Tool might not be able to install on iOS Mac Catalina (10.15) or later due to Apple’s third party developer block. In these Mac operating systems, an app fails to install because it hasn’t been notarized or is from an developer not identified by Apple.

Important MacOS High Sierra 10.3 is no longer receiving security updates. As a result, if you're having trouble installing the CPT on this version, our organization cannot provide a solution.

CPT delivered on a USB / downloaded

Go to System Preferences > Security & Privacy. Under the General tab, click Open Anyway to confirm your intent to open or install the app.

The warning prompt reappears, and you can click Open.

Note 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.

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.

If still facing difficulties, follow the instructions below:

Workaround 1

  1. Download the CPT.
  2. Unzip the CPT.
  3. Move app to Applications folder.
  4. Open the Terminal app.
  5. Enter the following command: sudo xattr -dr com.apple.quarantine /Applications/App Name.app.
    Example: sudo xattr -dr com.apple.quarantine /Applications/Life_BRE_2e_Elementary_v2.app
  6. Hit Return and authenticate with an admin/system password.
  7. Launch the CPT again.

Workaround 2

  1. Open the Terminal app from the /Applications/Utilities/ folder and then enter the following command: sudo spctl –-master-disable.
  2. Hit Return and authenticate with an admin password.
  3. Relaunch System Preferences and go to Security & Privacy and the General” tab.
  4. You will now see the Anywhere option under Allow apps downloaded from: Gatekeeper options.
  5. Control-click the CPT app icon, then choose Open from the shortcut menu.
  6. Click Open.
  7. Once the CPT is installed and can be launched, go back to Terminal app from the /Applications/Utilities/ folder and then enter the following command syntax to reestablish the initial settings by which Apple blocks all third party developer apps: sudo spctl -–master-enable.

Workaround 3

  1. Download the CPT.
  2. Double-click the .dmg or zip file to extract the app file.
  3. Move the app file from your Downloads folder to your Applications folder.
  4. Navigate to Applications > Utilities.
    1. Open the Terminal app.
  5. Copy and paste the following command:
    sudo chmod -R 755 /Applications/full_name_of_your_app.app

    Example with app name: sudo chmod -R 755 /Applications/Great_Writing_5e_L4_v1.app

    1. Hit Return.
  6. Enter the admin/system password.
  7. Copy and paste the following command:
    sudo xattr -dr com.apple.quarantine /Applications/full_name_of_your_app.app

    Example with app name: sudo xattr -dr com.apple.quarantine / Applications/Great_Writing_5e_L4_v1.app.

    1. Hit Return.
  8. Navigate back to your Applications folder and double-click the application.
    Note The application may take a long time to load, as the offline CPTs can be large files.

Legacy CPT delivered on a CD/DVD

Mac OS 10.15 Catalina and later operating systems do not support 32 bit applications. Our legacy CPTs delivered on a CD/DVD are 32 bit applications. For instructions on how to upgrade to the newest edition, please contact your sales representative.