This message can be issued if the SVC being used for the IDMS CV is not the most current SVC.
You could also get this message if you are using the latest SVC but if the order of the CSECTS included is not what IDMS expects.
If including the SVC exit program IDMSSVCX you must include the modules as follows:
Startup expects the CSECT IDMSMSVC to immediately follow #SVCOPT.
Some clients have included IDMSSVCX between #SVCOPT and IDMSMSVC and that will cause the DC170204 message at startup even though the SVC will function