This error may occur when Luminate does not have an API Key listed in its configurations. The new Service Center (Service Center 2) relies on making API calls in order to render the sustaining gift information in the constituents Service Center. For this reason, the "Convio API Key" field in Luminate cannot be NULL.

To resolve this error, an admin must take the following steps:
  1. Go to Setup > select Site Options
  2. Select the Open API Configuration tab
  3. Next to the first option, "Configure API Keys", click Edit API Key
  4. Under the first option, "1. Convio API Key", read the Convio API License Agreement terms and determine if you agree.
  5. If you agree, then enter an API key in the blank space. If you do not have an API key, then just enter APIKey in this field.
  6. Click Save
Have the constituent log in to their Service Center again. The error will no longer appear.