Symptoms

Trying to register the K2 for SharePoint app on all subsites in a site collection appears to work, clicking "Finish" at the end of the registration navigates back to the beginning of the wizard.

When trying to use the app, the error below occurs:

Server Error
Exception of Type 'SourceCode.SmartObjects.Client.SmartObjectException' was thrown.
 

Diagnoses

Enabling Smartobject logging captured the information below:

Thread 1: Cannot set Column 'Application_Full_Control' to be null. Please use DBNull instead.


Looking at the hidden list 'https:///portal.denallix.com]/Lists/K2 Settings' shows list items with Title column showing 'No Title' and Value column alternating between 'True' and '/K2Pages'.

When attempting to add a new item to the list, only the "Value" field is displayed, the "Title" field is not available.

 

Resolution

This is a result of the "Item" content type being modified so that the "Title" column is set to "Hidden" instead of "Required" or "Optional". Edit the "Item" content type at the Parent level and set "Title" to "Required" or "Optional", delete the "No Title" fields and re-run the registration wizard.