Neither QuickBooks Online or Xero will allow importing of invoices with the same invoice number. Therefore, as long as the invoice numbers are not adjusted from the download, only invoice data that has not been imported will make it through the QuickBooks Online or Xero importer tool. This is even if invoice data that had previously been imported was included in the export from Karbon.

Keep in Mind For QuickBooks Online it is essential that custom transaction numbers are enabled within the settings area.

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