1. Locate the Sales Journal entry that you wish to mark as bad debt. LEAVE THE ORIGINAL TRX ALONE, but note the job, billing item, cost code, amount, and invoice number.
2. Create a new Sales Journal entry to the above job, marked as Bad Debt.
Complete the Invoice Number as the original number plus the characters bd (or some such - 163453db, for example).
Period should be the current default period.
Amount should be positive - all or part of the invoice amount
GL Account in the child table should be your bad debt account, along with bill items, cost codes and gl entity from the original entry.
3. If you run aging at this point $'s will not reflect the bad debt write off. To clear up aging, however, you need one more step...
4. Go to AR Cash Receipt, and enter the Client Id, default period, zero amount in header.
In the lower section, select your orignal trx and your bad debt trx. Amount should sum to zero (if you are only marking part as bad debt, you will need to adjust the original trx amount in the middle.
Enter 'clean up' or some such in the Trx Description.
5. Save transaction.