Symptoms

A user try to create a custom filter but incorrectly so now the list does not come up anymore. How can I find the location of the filter and delete it since I can not delete it from the listview since it does not come up. See attaché the control he tried to use
 

Diagnoses

Data regarding each user filter settings is stored in Forms.UserSetting in the K2 DB. User ID corresponds to Form.User.Profile.
 

Resolution

Deleting the records from Forms.UserSetting fixed the issue.