Https://www.historycouncilvic.org.au/danna1996/error_3171_modifying_invoice_before_closing_date_in_quickbookshttps://www.historycouncilvic.org.au/danna1996/error_3171_modifying_invoice_before_closing_date_in_quickbookshttps://www.historycouncilvic.org.au/danna1996/error_3171_modifying_invoice_before_closing_date_in_quickbookshttps://www.historycouncilvic.org.au/danna1996/error_3171_mo... https://www.historycouncilvic.org.au/danna1996/error_3171_modifying_invoice_before_closing_date_in_quickbooks