How to manually close a PO
Normally, PO's do not need to be closed manually. The system can automatically close a PO if all lines of the PO have been received and full and then all of those receipts have been invoice-matched in full.
That said, occasionally you may need to manually close a PO. To do this, first make sure all PO detail lines are closed under (Purch > Purchase Orders > Detail tab > 'Line Status' column). After all of the detail lines have been closed, you can then close the overall PO by changed the status in the 'Header' tab to CLOSED.