Data Management Capabilities > Managing Part Structures > Product Structure Explorer > Checking Out an Object > About Occurrences and Reference Designators > Adding or Editing Occurrences
  
Adding or Editing Occurrences
To add or edit a reference designator for an occurrence of a part, use the following procedure:
1. Select the Uses tab in the right pane.
2. Enter a value in the Reference Designator column.
Use BOM view to edit the reference designator as a range. If the quantity of the part is increased or decreased as a result of editing the range, a window appears asking if you want to adjust the quantity of the part accordingly.
or
Use occurrence view to edit each individual reference designator
The new designator appears in the table.
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If you are in edit mode of Product Structure Explorer, check out the parent of the part for which you want to add the new reference designator. Then the attribute becomes editable. Occurrence mode is the default mode for Windchill MPMLink.