Go to System → Settings → Checkout
Set the starting number the orders ids will begin from. The next order placed will have the new numberinitial number for your order IDs. This determines the starting point for new order numbers.
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This setting is important to avoid Avoid conflicts with previous orders placed with some specific payments , especially when using payment methods like PayPal. PayPal will reject any transaction with an order ID that has been used beforerejects transactions with duplicate order IDs. |