Actually, it's not easy to duplicate the values for the index tag or filter, as those are both based on selections made during execution of the form.

However, I'm happy enough with the solution of simply removing the index tag and filter before ZAPing, if they could be the cause.

>>No memo fields -- but there was an index tag and a filter.
>>
>>After removing both the index tag and filter before the ZAP, the error does not seem to recur.
>
>We're getting somewhere. What were the expressions in these two?