How to Tell if an Invoice Has Been Emailed in QuickBooks. If you need to determine whether you previously sent a specific invoice to a certain customer, you don't have to rely on your memory.

For emailed invoices, the invoice is sent to a Centsoft email address and the invoice is processed in the cloud.

QuickBooks automatically sets your invoice number and increases it sequentially with each new invoice, but you can adjust this number to anything you want. Setting your own invoice number can help ...