Cashbook Bank Management – Value Exists In The PM_Key_MSTR Table

Microsoft Dynamics GPA client had an odd error with the Cashbook Bank Management module the other day when trying to enter a deposit; the following was printed on the exception report when trying to post the transaction:

Value exists in the PM_Key_MSTR table

I did some digging around and found that the Next Voucher Number field in Payables Management Setup – Options (Microsoft Dynamics GP menu » Tools » Setup » Purchasing » Payables Setup) was blank.

I set a new value in the Next Voucher Number field and the deposit could be posted without problem.