CRM 2013: Condition for attribute 'template.templatetypecode': null is not a valid value for an attribute. Use 'Null' or 'NotNull' conditions instead.
Lately I was fighting with an issue that on some CRM instances the default email templates view in the Templates section of CRM 2013 did not show up and only showed me this error message: Condition for attribute 'template.templatetypecode': null is not a valid value for an attribute. Use 'Null' or 'NotNull' conditions instead. After searching for a long time I found the simple bug. Throught migration from 4.0 to CRM 2013 over CRM 2011 and changing customizations it seemed that CRM got messed up or was not able to handle the changes very well. The issue here was to go to the views section of the Email Templates entity and to make sure there is only ONE default public view. If there are two you will get strange system behavior. I fixed this problem through updating the isdefault property of the second unwanted default view in the SavedQueryBase data table. The id of this view you can retrieve by openen the view and by copying it out from the URL. Én voi