Source:  NWCONFIG.NLM

Explanation:  A Media Manager call failed. There might be a hardware or driver problem, or there might be an inconsistency between the partition table and the disk geometry.

Action:  Make sure drives are online and drivers loaded. Look for disk or driver problems. Try setting the server parameter Ignore Disk Geometry to On. (Load MONITOR.NLM and select Server Parameters > Disk > Ignore Disk Geometry.)