We need to change the "Primary selection field in 'Maintain Deliveries' as "Picking list Number" from "Order Number" in Maintain sales order parameters. Before apply the changes, i have following questions.

1. What will happen to the old pending orders (waiting at Maintain deliveries stage) which are not having order step as "Print picking list".

2. Is there any correction session available to correct the pending sales orders steps.

(I have tried the above with test environment and i could not deliver the sales order that are not having picking list as order step. System simply hangs until I revert the parameter to "Order Number").

Please help.

Regards.

I think you have answered your own question.

The correct procedure would be to create a new order type including the Print Picking List step. Let the old orders work out of the system. Then change the Maintain Deliveries selection to Picking List Number.