When you say "outstanding balances", do you mean unpaid invoices or do you mean uncollectible accounts? If it's just unpaid invoices that are collectible, there's nothing you need to do and nothing you should do. If you reissue invoices and your business uses the accrual method of accounting, you will be shifting income and that's bad. And, if you're on the cash method of accounting, it makes no difference whether you reissue the invoices or not as income is recognized when the customer pays, not when the invoice is issued.
If these accounts are deemed uncollectible, you can expense them to 'bad debt expense'.
