Un-cancel a Sales Order

If a sales order is cancelled the order is considered as closed and you can’t reopen the order. Users need to use the [copy order] button to copy the order as a NEW sales order.

Once a sales order is cancelled there isn't a way to reverse that. Instead, you'll need to copy the sales order as a new order. You can do that with the following steps:

1. From the cancelled sales order, click the "Copy" button.
2. Select between "As Quote" or "As Order" to copy the cancelled order as a quote or an order. (You can also use Ctrl + Shift + Q to copy as a quote, or Ctrl + Shift + N to copy as order without even having to open the copy menu!)
   1. 
3. You'll receive a confirmation to copy the new order as the customer used on the current order. Click "Yes"

Once the sales order is copied, you can make any modification needed and save the order.