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If the credit note is generated based on the invoice, this tab is automatically populated - remove the lines that you don't need and leave the lines with returned items or the items for which correction is needed and edit the details. You can use the Up and Down ( 
) arrows to rearrange the items in the list.
If you need to manually add an item or multiple items, click the Add button on the tab toolbar.
In the Quantity column, you can specify the item quantity and in the Unit column, you can select an UOM for the item if the Multiple UOMs per Item option is selected on the Administration > Settings > Purchasing and Warehouses form.
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The Serial Numbers column is available if the Use Serial Numbers option is selected on the Administration > Settings > Purchasing and Warehouses form. For each serialized item (for which the Use Serial Numbers check box is selected on the Items form), click in the column to open the Serial numbers dialog box. In this dialog box, you must enter the serial numbers according to quantity of the returned item.
You can specify the Discount for the inventory or service item if the .
The Discount,% and Discount (or Discount Price) columns are available if the Enable discounts and markups in sales documents option is selected on the Administration > Settings > Sales form. Use these columns to specify the discount that was used for the inventory or service items in the basis (original) document.
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