EXPLANATION This message should occur only on a down-level computer. Any action to correct the problem should be performed ...

EXPLANATION    This message should occur only on a down-level computer. Any action to correct the problem should be performed on that computer.  An unexpected network control block (NCB) error occurred  on the session with the specified server. The server may have been restarted, or a network problem may have occurred.    ACTION    Ask your network administrator if the server was recently restarted.    If you need more assistance, contact technical support. This message displays an NCB value and the NCB error that was returned. Save this information for technical support.