If your Google Add-ons are not working as expected or if you are unable to install Google Docs add-ons from the Chrome store, it is likely that your Google Apps admin has disabled the setting that allows domain users to use add-ons.

Here’s how they can enable add-ons for your Google Account from the Google Apps admin dashboard.

Step 1 - Login to your Google Apps admin console at admin.google.com

Step 2 - Go to Apps -> Google Apps -> Drive and make sure the status is “ON” for everyone.

Step 3 - Go to Apps -> Google Apps -> Settings for Google Drive -> Data Access and enable the following settings.

• Drive SDK (Allow users to install Google Drive apps) Google Drive apps allow users to open their files in web apps installed from the Chrome Web Store.
• Add-Ons (Allow users to install Google Docs add-ons from add-ons store) Docs add-ons allow users to use Docs features built by other developers.

The Admin console setting for add-ons controls Docs, Sheets, and Forms; there are not separate settings for each document type.