The background delivery creation from transaction VL10B calls the parallel processing which cannot be debugged directly. Even if breakpoints are kept in all relevant user exits , the debugger wont be called.
Consider the below Purchase Order in ME23N for which an outbound delivery needs to be created:
In order to create outbound delivery , we are using VL10B here.
We need to select the required PO line item and then click on background. At this stage, the delivery would be created without entering the debug mode in spite of keeping breakpoints in delivery user exits.
As a solution to this, we will have make small settings, so that we can reach the required breakpoint in delivery user exit.
In SU3 settings insert parameter LEDSP_DEBUG_MODE and enter the value “VL10B”.
Now , we are ready to create the outbound delivery via VL10B.
As mentioned above, when we select the required PO and click on Background:
The debug mode would get initiated and processing would stop at a random BREAK statement in standard code. At this stage, from the debugger menu we need to choose BREAKPOINTS–> BREAKPOINT AT –> BREAKPOINT AT SUBROUTINE.
Now enter the required program and subroutine name of the delivery process where you want the debugger to stop.
After clicking on OK. Press F8 until you reach the designated program SAPMV50A–>USEREXIT_SAVE_DOCUMENT_PREPARE
Now you can debug as per your requirement and outbound delivery would also get created successfully.