1.  In Cash Receipts, record the check as a payment so that it is posted to the General Ledger as well as entered into the bank account's register.
  2. In Accounts Payable, Records, Vendors, open the Vendor record.
  3. Create an invoice with today's date for the refund amount.
  4. Create a credit memo with today's date for the refund amount.
  5. Set both of these transactions to Do Not Post.
  6. Apply the credit memo to the invoice. 

These steps allow the Vendor record to reflect the credit without creating a credit balance, while the Do Not Post status prevents duplicate information in General Ledger.

The Cash Receipts posting verify the check is properly recorded in General Ledger.