Data & AssessmentAssessment Scanning Teacher SetupUnable to install Gradecam on a Mac - 'GradeCam is from an unidentified developer' error during installation

Unable to install Gradecam on a Mac - 'GradeCam is from an unidentified developer' error during installation

This lesson will guide you through the process of overriding Apple's Gatekeeper program to install the GradeCam plugin for Mac.

What is Gatekeeper?

Some apps downloaded and installed from the Internet could adversely affect your Mac. Gatekeeper helps protect your Mac from such apps. Read this article to learn about Gatekeeper and its options.

Gatekeeper is a new feature in Mountain Lion and OS X Lion v10.7.5 that builds on OS X's existing malware checks to help protect your Mac from malware and misbehaving apps downloaded from the Internet.

The safest and most reliable place to download and install apps is via the Mac App Store. Apple reviews each app before it's accepted by the store, and if there's ever a problem with an app, Apple can quickly remove it from the store.

For apps that are downloaded from places other than the Mac App Store, developers can get a unique Developer ID from Apple and use it to digitally sign their apps. The Developer ID allows Gatekeeper to block apps created by malware developers and verify that apps haven't been tampered with since they were signed. If an app was developed by an unknown developer—one with no Developer ID—or tampered with, Gatekeeper can block the app from being installed.

GradeCam does not have a Developer ID, nor do they plan on getting one. That means, if you have Gatekeeper set up to only allow you to download applications from the "Mac App Store and identified developers" or "Mac App Store" you may have trouble installing the plugin. Please see the steps below to temporarily or permanently override Gatekeeper to allow you to install the GradeCam plugin.

Where to start

Where to start

Gatekeeper options are found in Apple menu > System Preferences > Security & Privacy > General tab under the header "Allow applications downloaded from:"

Temporarily overriding Gatekeeper to install the GradeCam plugin

Temporarily overriding Gatekeeper to install the GradeCam plugin

If you have GateKeeper configured to only allow installation from the "Mac App Store and identified developers" the operating system will prompt you with a message like the one above when you try to install the GradeCam plugin.  

  1. Click on the "OK" button to dismiss the warning. The plugin will not be installed.
  2. Right-click (or hold the control button on your keyboard while clicking the mouse) on the "Install the GradeCam Plugin.app" icon to bring up a contextual menu.
  3. Choose "Open" from the contextual menu. This will pop up a modified version of the previous warning with two options instead of one.
  4. Click on the "Open" button to install the GradeCam plugin.

Using this option, the next time you try to install an unsigned program, Gatekeeper will prevent you from completing the installation. If you want to permanently change your settings, read on!

Permanently overriding Gatekeeper to install the GradeCam plugin (and all other unsigned software)

Permanently overriding Gatekeeper to install the GradeCam plugin (and all other unsigned software)

To permanently change Gatekeeper's settings, follow these steps:

  1. Open the System Preferences program by clicking on the Apple Menu and selecting "System Preferences".
  2. Click on the Security & Privacy preference pane.
  3. Click on the lock at the bottom of the window and enter your password to enable changes to these preferences
  4. In the "Allow applications downloaded from:" section, select "Anywhere."
  5. The system will prompt you that "Choosing 'Anywhere' makes your Mac less secure." Click "Allow From Anywhere" to make the change. You will now be able to install unsigned programs.

Next Step

Try scanning again.  Use the "Scan Student Responses with GradeCam" lesson if needed.  

If you are still unable to scan, please view our "Scanning Troubleshooting" help document for further assistance.