I am facing an error in communication channel while trying to post the file to the FTP server,
The error is " Message processing failed. Cause: com.sap.engine.interfaces.messaging.api.exception.MessagingException: An error occurred while connecting to the FTP server '10.100.5.00:20'. The FTP server returned the following error message: 'com.sap.aii.adapter.file.ftp.FTPEx: 501 Unknown error'. For details, contact your FTP server vendor"
Please could you advice what need to be done to resolve this.