Hi @Ramesh Selvaraj Greetings! Welcome to Microsoft Q&A forum. Thank you for posting this question here.
FTP and SFTP protocols operate on different ports. FTP uses the port 21 for command operations and 20 for data operations while SFTP uses 22 by default. If SFTP is enabled on your on-perm machine, you can make connections to it over port 22. If you plan to use FTP, make sure the corresponding port is open and try connecting.
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