adding the delivery subject line to a standard report like this:
leads to this error:
and I can't figure out why. Any other attempt to display the subject line within a report has failed so far.
Does anybody know how to fix this?
I think that you have to add a grouping clause to your query:
<groupBy> <node expr="@id" label="Subject"/></groupBy>
<node expr="@id" label="Subject"/>