To Remove a Division Definition From a Door and Window Assembly Style
Use this procedure to remove a division definition that you no longer need. You cannot remove a division definition that is currently assigned to a grid. In addition, you cannot remove the default division definition, but you can modify it.
Note: Alternatively, select a door/window assembly in the drawing, and click Door/Window Assembly tabGeneral panelEdit Style drop-downDoor/Window Assembly Styles.
Select a door/window assembly style.
Click the Design Rules tab.
In the left pane, select Divisions under Element Definitions.
Select the division definition that you want to remove.