If you're importing Purchases, you have the option to reject duplicate transactions or add them to your company file. (How to handle duplicate records when importing) When you import purchases, each purchase will be checked for duplicates according to your selection. (Preferences window -- Purchases view)
In this window you can choose to warn for duplicate purchase order numbers only, vendor invoice numbers only or warn for either duplicate PO numbers or duplicate vendor invoice numbers. When you import purchases, each purchase will be checked for duplicates according to your selection.
If you've marked the preference Warn for Duplicate Purchase Order Numbers, imported purchases will be checked for duplicated purchase order numbers only. If you've marked the preference Warn for Duplicate Vendor Invoice Numbers, your imported purchases will be checked for duplicate vendor invoice numbers only. If you've marked the preference Warn for Duplicate PO and Vendor Invoice Numbers, your imported purchases will be checked for either a duplicate PO number or a duplicate vendor invoice number.
If you haven't marked the preference, each purchase will be checked for either a duplicate PO number or a duplicate vendor invoice number; that is, your imported purchases will be checked as if you had selected Warn for Duplicate PO and Vendor Invoice Numbers on Recorded Purchases in the Preferences window.
If the Purchase Order or Vendor Invoice field is blank, the field is not considered a duplicate.
If you choose to reject duplicate records, the information that's rejected will be placed in the Import Log report, which is created at the time you import.