External Content Types are not available. Contact your system administrator

When creating an external list in a SharePoint site I clicked the Select External Content Type button and received the following error:

External Content Types are not available. Contact your system administrator.

This happens because no external content types have been created within the site.  If external content types have been created then the user may not have the appropriate permissions.  To grant permission to external content type follow these steps:

1. In Central Administration, under Application Management, click Manage service applications
2. Click on the Business Data Connectivity Service
3. Check the box next to the required external content type and click Set Object Permissions in the ribbon
4. Add the user(s) that require access to the external content type and grant the appropriate permissions.  Click OK
   

Note: External Content Types are created using SharePoint Designer.