You can use one of the following three methods when deleting a C1AutoCompleteDataItem in the designer:

• Deleting a child item through the shortcut menu
  Right-click the C1AutoCompleteDataItem you wish to delete and select Delete.
  
  
• Deleting a child item by pressing on the delete button
  Select the item you wish to delete and click on the Delete.
  
  
• Deleting a child item through the Edit menu.
  Click the Edit menu and select Delete.