This document explains the error AccountIdNull when converting from Order to BILL in MYOB.
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 an MYOB bug and need to tick all items as:
3. Assign account to EXPENSE and INCOME > set TAX CODE.
4.. Convert to BILL.
5. Please set up all new items as I BUY, I SELL, I INVENTORY to avoid this issue in the future.