I have used "Send file over FTP" smart services to transfer one file t

There are some useful articles that give you ideas. Looks like a misconfiguration of the node:

forum.appian.com/.../kb-1172.html
forum.appian.com/.../kb-1114.html
forum.appian.com/.../kb-1113.html

Thanks @eduaro I will cross check the configuration...
Do you have any idea to find the "server logs" in logs folder?

You will find all logging info - forum.appian.com/.../Logging.html

For On-Premise: <APPIAN_HOME>\\logs\\application-server.log
For Cloud: jboss1-stdOut.log.yyyy-mm-dd

Thanks @sagar and @eduardo.. I have a doubt like can we transfer a file to remote which is not in same network. Have we need to change the firewall settings for this transfer to be happen? or Can we send directly using smart services "Send file over FTP/SFTP" If the Remote server is global which can be accessible from Internet. Kindly help on this

@Arun - You can transfer file over different network but you can't use the smart service directly. You have to make some firewall settings to allow the incoming connection over FTP and an inbound rule for port 21.

You can test your ftp connection here - www.wftpserver.com/onlineftptest.htm. It will get you logs to view each and every detail regarding the connection.

@arun
Is your issue resolved i have an same error for my application and I m frustrated. If your issue solved can u please let me know the root cause

I faced the same issue and got it resolved by performing several online and offline tests on ftp server. Yo can use the link - www.wftpserver.com/onlineftptest.htm to connect your machine via ftp remotely and for offline test, you can download winscp to check the connection.
Also the hostname I was taking was the machine's name instead of the public ip address of the machine. So try with public ip address in the setup and make sure the third party credentials you are using are correct.

Thanks varnikam,
the URL which u shared in not working .. Always it is throwing error even for Valid FTP credentials