Why is there an 'null input to JSON Parser'

Issue:

When navigating to the related list of a Media Campaign, the following error was shown “An error occurred null input to JSON Parser”:

Open

Solution:

• Check the Feature Settings values related to Campaign Item Related List, CIRL takes the values in order to show the buttons and columns, so something is null or missing in the feature setting

• More information can be found: 8.5.4 Settings for the Custom Campaign Item Related List