3211 Unknown identifier found in conditional index expression

Advantage Error Guide

Problem: An error occurred in the Advantage Expression Engine parser. An identifier within the conditional index expression is unknown to the parser.

Solution: This error is usually caused by the use of memory variables within the conditional index expression. Memory variables are not supported by the Advantage Expression Engine as the variables are visible only to the client. This error may also result from a misspelled field name or from a field name that does not exist in the current work area.