Set the control flag Default_To_Picklists to yes via the following steps:
Click Options, System Maintenance, System Settings, General System Settings
Click Control File
Enter Default_To_Picklists in the Control Item field
Press Ctrl + M to modify
Change value to Yes.
Then, amend the user access permissions as follows:
Select Options
Select User access
Select relevant user and press F5 to zoom in
Click View access
Select Sales tab
Make sure the check boxes create, modify, delete and access for Delivery Notes are all selected
Click OK
