About opening balances
Opening balances are simply the amounts in your accounts at the beginning of your conversion month. (Your conversion month is the month in which you begin using your MYOB software.) It's important to enter your accounts' opening balances accurately and completely to ensure that your financial reports accurately reflect the state of your business.
If your conversion month is the first month of your financial year, you'll need to enter opening balances only for your asset, liability and capital accounts. If you begin using MYOB Accounting Plus in any other month, you'll need to enter opening balances for all your accounts.