As per standard functionality, it is not possible to send notifications to other non-PO users whenever a PO receipt is approved .
Standard functionality says that PO Confirm Receipts workflow can be used for sending receipt notifications to requesters or buyers notifying them that they should have received their order.
The Confirm Receipts workflow sends notifications through the Web, e-mail, or Notifications Summary window to requesters or buyers who create requisitions through Purchasing or Oracle iProcurement. It lets people know they should have received an item.
The Confirm Receipts workflow sends notifications for items with a Destination or Deliver-To Type of Expense, a Routing of Direct Delivery, and a Need-By date that is equal to or later than today's date.
This workflow requires that the Workflow Background Process process be running.
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