Microsoft Dynamics GP
You cannot receive against unauthorised purchase orders.
It took me a little thought to determine what the error might be. The client had rolled balances forward into the new year and imported the relevant budget, but had not set the budget within PO Commitments.
This is done via the PO Enhancements Setup window() and clicking the Commitment Setup button:
As you can see, in the below screenshot, there is a Budget ID selected for 2016, but not for 2017 (the client operates their Fiscal Calendar on a year starting basis).
Adding the missing budget, allowed receivings transactions to be entered and UAT to progress.