Is there a way to default the Reserve checkbox as RESERVE in Requisition form?

Hi all,

We are in R12 and our accounting is based on Encumbrance accounting.

I need to default the "Reserve" checkbox to checked when the user enters the requisition and clicks on the "Approve" button.

Is there a setup that could be done?

I tried doing it through custom library, I was able to make the "Reserve" checkbox to checked, but when I click the "Ok" button on the "Approve Document" screen, it comes back with "No data found". Basically we are trying to force this checkbox to be checked, so that the Funds are reserved before going to the next level.