We use the extRefID field to mark system objects that have been processed by a custom e-mail parsing system. It would be very handy if we could update the extRefID field for a journal entry, but this failed when we attempted it. It seems odd that there even would be a extRefID field if access to that field is locked.
I'm looking for any input as to how we might modify this field or workaround that others have implemented.
Journal Entry is a system object as has no Edit or Add end point so it is not possible to create or edit a Journal entry through the API only the System can create these.