Symptoms

SmartObject not removed from K2.Category.Data table
 

Diagnoses

When going into a workflow to amend a SmartObject call, and when trying to expand the SmartObject folder, the following error appeared: "SmartObject does not exist on the server" (with a GUID).

Some old SmartObjects have been deleted from a project recently,
 

Resolution

It could be the case that there are two smartobjects that were deleted initiall within the k2.smartbroker.smartobject table but still existed within the k2.category.data table. Redeploying the smo's and then deleting them via the workflow folder containing theses smart objects should resolve this error.