Check that the Journal, Sales Account(s), and the Customer charges tax by reviewing the Trade Information of each item.

If you cannot exit the application database because of this error or this error occurs each time you enter the application database, check the Sytem > Audit folder on the left explorer tree for the transaction and on the window below select Basic or Advanced to view the transaction changes and set the transaction back to it’s normal state and then review the Journal, Sales Account(s), and Customer Trade Information for the tax settings.