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When adding timber parts to your Part List, you may encounter this error message:
"Material [material name] is already specified on part [part number and name] for the [group name] group in this category. Material must be unique within the group."
This happens if there is already a part of this material in the Group which you have selected. Group is the subcategory selected next to Category. In this example the Category is Surround > Internal Architrave and the Group is 3 inch Ogee:
The solution is to either select a different material for the part, or selected a different group. You can also create a new Group from the drop-down menu:
