Quectel WCDMA UG FTP Series At Command Manual page 43

618 Requested action aborted: local error in processing
619 Requested action not taken: insufficient system storage
620 Syntax error, command unrecognized
621 Syntax error in parameters or arguments
622 Command not implemented
623 Bad sequence of commands
624 Command parameter not implemented
625 Not logged in
626 Need account for storing files
627 Requested action not taken.
628 Requested action aborted: page type unknown
629 Requested file action aborted
630 Requested file name invalid
631 SSL authentication failure
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WCDMA UGxx FTP AT Commands Manual
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