Once a voucher (a manual check or an AP invoice) has been posted, it cannot be changed through the Manual Checks or AP Invoices screens. While it can be voided and recovered, the following are changes that can be made to posted vouchers without voiding them:
If you have applied a voucher to the incorrect vendor, you can correct the problem by entering a credit memo to reverse the original transaction, then re-entering the voucher for the correct vendor code.
When entering the credit memo, you should use all the same information as the original invoice, including the same incorrect vendor number, invoice date, apply date, GL account, and dollar amount. If you have Compeat set up to allow duplicate invoice numbers (specified under Other Definitions > Invoice & Check Settings), you can use the same invoice number; otherwise, you can add characters (such as "CM") to the invoice number to make it unique, yet still references the original invoice.
We recommend that you use the same apply date for the new credit memo and re-entered voucher, so the expenses are kept in balance for the current period.
Correct a GL Account If you have applied a voucher (all of it or any portion of it) to an incorrect GL account number, you can correct the problem by making General Journals entries, crediting the incorrect account, and debiting the correct account. The apply date of the general journal entry should match the apply date of the voucher.
For example, if you applied a voucher for Produce to 4510-000, and it should have been applied to 4550-000, you would make a general journal entry that credits 4510-000, and debits 4550-000.
Correct a Duplicate Voucher If you have entered a voucher twice, you can void one of the vouchers using either the feature Void Invoices/Credit Memos or Void Vendor Payments .
Note: You cannot void a voucher that has been paid unless the check that paid the voucher is first voided. You also cannot void a voucher that is in an unposted payment batch until that batch has been deleted or the voucher has been removed from the batch.