ftp 501 Option not supported

This error message is usually encountered when attempting to use an FTP command or option that is not supported by the FTP server. It could also be caused by a firewall or other network device blocking the command or option.

To resolve this issue, try using a different FTP command or option, or check with the server administrator to ensure that the command or option is supported. You may also need to check your network settings and ensure that there are no restrictions or firewalls blocking the FTP connection