ZCOPT0, External call: Qualifier OPTIONAL_0 can be used only with mechanisms REFERENCE or DESCRIPTOR

Run Time Error: This indicates that an external call or $ZCALL function encountered an external call table input line that contained an OPTIONAL_0 QUALIFIER with a MECHANISM other than REFERENCE or DESCRIPTOR.

Action: Verify the type and spelling of the specified argument-passing mechanism in the external call table entry.

inserted by FC2 system