SOLUTION: "An error occurred when attempting to load this plug-in"

If you are attempting to add Negative Lab Pro to the Lightroom plugin manager, and you get the error message “An error occurred when attempting to load this plugin,” please read on for the solutions.

In most cases, the problem is from trying to load the INSTALLER package itself into the plugin manager. The installer package is not a plugin, so this will not work.


  1. If you haven’t already, you need to RUN the installer package. You run this like any other installer, by double-clicking it from the Finder application in Mac. The installer package does a number of steps for you, such as extracting the plugin to “Users/{yourusername}/Plugins”, adding camera profiles, and adding the keyboard shortcut.

  2. In the plugin manager, you need to find the plugin file (which will have an extension of .lrplugin). You can do this by navigating back to your home directory, which will be your username (in my case, it is “nathan”). You can get there quickly by clicking the dropdown menu at the top of the plugin manager file dialog box, and selecting your username.

  3. Then, navigate to the Plugins directory.

  4. Inside, you will see the NegativeLabPro.lrplugin file. Add this.

Why is it so complicated?

It shouldn’t be so complicated. Apple made a change in a recent OS that is adding some complication. I’m working on fixing this installer for the next version to work better with more recent OS guidelines.