validation on purchase order

Hi Team,

We are on WS 7.3 cum 10. We came across one scenario raised by user where they want some validation while raising purchase order such that if vendor is inactive then system will not allow to create purchase order. Is this possible in std. jde? If yes then how? Also, few purchase orders already created for inactive vendors which causing issues while allocating invoices to vendors for those purchase order. So is that possible if still we receipt those purchase orders or we need to cancel those? If order is already received then what can be done?

Thanks,

Sagar