Purchase invoice processing should be allowed even after the project stage finished, if the parameter "Prevent project closure if open transactions exist" is enable as 'No' .

i.e., if we don't enable this parameter then system is allowing to update the Project stage closed/finished even though there are unposted transaction exist but it is contradicting to another validation which not allows to post the purchase invoice once the project stage finished.

so this parameter "Prevent project closure if open transactions exist" can't be set as 'No' which is irrelevant.

These changes are added from MS in reference to KB 4498630