The expression "%1!s!" on "%2!s!" evaluated to NULL, but the "%3!s!" requires a Boolean results. Modify the error row disposition ...

The expression "%1!s!" on "%2!s!" evaluated to NULL, but the "%3!s!" requires a Boolean results. Modify the error row disposition on the output to treat this result as False (Ignore Failure) or to redirect this row to the error output (Redirect Row).  The expression results must be Boolean for a Conditional Split.  A NULL expression result is an error.