If columns are added the the Customers sheet, then the VBA driven import will not fill those columns. For importing from Outlook, the best method is to first export the contacts as a CSV. Then use the batch import tool on the Control sheet to import the CSV. Here, you can move the columns up and down to match those required by the invoicing system. Reimporting this way will also update customer information where changes are detected and customer information can also be exported back to CSV and imported to Outlook.