Here is the difference between between “Voiding” and “Closing” transactions
Voiding Transaction: If we click on void button automatically order quantity will become “Zero” and transaction amount will become “Zero” and in memo field by we will get message called “VOID”
Note: - Void button will be visible only after editing sales order
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Closing Transaction: If we click on close order button order will be closed by checking the closed check box in line level, but quantity and total will same as order.