If you notice that sometimes, you are getting duplicate orders exported to QuickBooks, please check your Internet connection and make sure the export completes without error.
The way Teapplix export orders to QuickBooks:
1) send a batch of orders to QB for export
2) receive from QB confirm that these orders are exported, with sales number
3) record that these orders are exported
Under one scenario, Internet connection is lost between QuickBooks and Teapplix after 1). When this happens, QuickBooks tries to send confirm to Teapplix for a few minutes, and then gives up.
This will cause Teapplix to not know that this batch of orders (up to 100) is alreay exported. Next time, Teapplix will re-export the same orders, even though during the first try these orders have already been exported.
To avoid this, make sure your internet connection is solid. If you are exporting orders to QuickBooks for shipping, it's best to watch the export complete and make sure no error happens. If you run into an error that cause an order to be in QuickBooks but still in "Unexported orders" queue in Teapplix, you should remove that order from Teapplix export queue.