Issue in Picking List Posting

i am facing an issue in Sales Order Picking List.
once i post a picking list, Picking List, Picking List Registration both the buttons in Sales Order gets disabled, due to which we cannot able to post Packing Slip. How to enable Picking List Registration button?
Note: After posting Picking List the buttons get disabled and Picking List Journal is also not created.

I have checked the Accounts Receivable Parameters, where Default Order Type is ‘Sales Order’ & Picking Route Status is “Activated”.

Can any one please help me in this?

Two issues, one is the non-production of the pick, then the disabling which is probably related to your first issue. You will need to debug and work out why it is doing this - any customizations?