When a purchase order is printed, two things happen: the purchase order is marked as printed (preventing it from being printed again by the Print Purchase Orders menu choice) and changes to the purchase order are prohibited.
For auditing and convenience purposes, purchase orders are normally only printed once. The standard printing menu choice, Print Purchase Orders, only prints purchase orders that have not already been printed. If a purchase order must be printed again, the menu choice Reprint Purchase Orders, can be used. This menu choice allows a purchase order to be printed over and over.
Once a purchase order has been printed, all changes to that order are prohibited when using the Purchase Order menu choices, Purchase Orders or Non-Inventory Purchase Orders. The reason for this is two-fold. First, from an auditing standpoint, once the purchase order has been printed, it is sent directly to the vendor. Therefore, it does not make sense to allow changes to the order at this point.
The second reason for not allowing changes stems from how the purchase order is used. The purchase order is used as a basis for making receiving slips and vouchers. If changes were allowed, future receiving slips and/or vouchers might not be created correctly.
Still, there are times when a printed purchase order must be changed. To allow for this, two additional menu choices are provided: Edit Purchase Orders and Edit Non-Inventory POs. These data entry forms permit changes to any purchase order.