How to cancel a Sales Order prior to raising a Production Order
Select into the Order
To make order inactive, untick [Active] in Order Details
If you are unable to deselect "Active" you will need to inactive any subdocuments created before making the Sales Order inactive
[Save and Close]
The order is now inactive. Hidden from your list and removed from all calculations for production and raw materials.
If you want to see or recover this Sales Order, remove the filter for 'Active' only..
..and the order will be showing in your list with a line through it.
If you would like to report on Cancelled Orders, you can create an order tag 'CANX ORDER' and change as appropriate. read here about Sales Documents Settings - SO Tags