I have an amount showing in the non-taxable column on the Sales Tax Summary Report.  We did not have any tax exempt sales during the period in question so I'm thinking an error was made when one or more invoices were entered in Quick Billing.  Is there a way to do a search or print a report that shows which invoice(s) have been entered as "non-taxable"?  I've tried searching the KB but didn't come up with anything helpful. Any suggestions would be appreciated.