Server Administration > Item Type Attributes > Deleting Constraints > To delete a constraint in the GUI
  
To delete a constraint in the GUI
1. Right click the type with the constraint you want to delete, and then select Edit Type from the shortcut menu. The edit Type view opens.
2. From the left tree pane, select the Constraints node. The list of constraints is displayed in the right pane.
3. Select the constraint you want to delete and click Delete. The Delete Constraint dialog box prompts you to confirm the operation.
4. Click Yes to continue. The constraint is removed from the list.
5. You may continue editing the type, or click OK to save the delete operation.
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Changes to a constraint do not take effect until the associated type has been saved (that is, until you click OK in the edit Type view). If you cancel your edits to the type, your constraint changes are also canceled.