Description
This document explains the error AccountIdNull when converting from Order to BILL in MYOB.
Detail Steps
Error message as below when doing a conversion in MYOB, which is an MYOB known issue.

2. If getting error below'AccountID NULL' in MYOB while converting, this is a myob bug and need to tick all items as:-
I BUY
I SELL
I Inventory
3. Assign account to EXPENSE and INCOME - set TAX CODE.
4.. Convert to BILL.
5. Please set up all new items as I BUY ISELL I INVENTORY to avoid this issue in future.
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