Xerox 490 - Manual (Page 250)

Server and Input Function Xerox 490/980 Color Continuous Feed Printing System
13-16 Printer & PC GUI Guide
Common errors
Response message Description
451 Error in server: local error. An internal error occurred in the idle state.
451 Error in server: Internal error. An internal error occurred during command
processing.
221 Closing connection due to server error. EBCDIC is not supported.
421 Service not available, closing control connection. A control connection was disconnected
because an FTP server connection service
forcible-stop instruction was received or the
system shut down.
421 Timeout (%d seconds): closing control connection. A control connection was disconnected
because time-out occurred.
500 'command': command not understood. The command is not described in RFC959.
502 command not implemented. The command is not mounted, but
described in RFC959.