It's the InstrumentNo property that you need to set.

(When you're entering a journal manually in Sage 200 you're actually populating a PendingNominalBatchEntry which *does* have a BatchReference - but this just gets used to populate the Instrument objects when you post it).

Hi Chris, I was expecting it to generate reference number just like this. I tried set InstrumentNo = next journal reference number, but the reference column still empty.

Ah...I missed an important step.

What you have to do is set the InstrumentNo property of each item in your instrument's NominalJournalInstrumentItems collection.

thank you that works. Looks like I have to prepend the "J" to reference number myself.

I've just checked and yes, you do.

(I'd never really thought about that before but it could be quite useful if you want to differentiate transactions which have come from an external source)