If a field of Criteria is not going to be needed any more, delete it. To delete a field, first open DataForm.NET Manager. Choose a DataForm id in DataForm.NET List, the fields of that Criteria will be displayed in the Criteria tab. Click "Delete" icon to remove field from Criteria. The distinction between "In use" and "Delete" is that if a field's "In use" property is not checked, it is disabled but the settings are still in Criteria, it can be enabled later. However, a field is deleted, then all of its settings are gone.