FluentFTP with Azure FTPS

I’ve just tried to connect to Azure FTPS site using FluentFTP library. Local FileZilla server tests were passed successfully but Azure FTPS connection fails.

Error looks like

System.IO.IOException: Authentication failed because the remote party has closed the transport stream. at System.Net.Security.SslState.StartReadFrame(Byte[] buffer, Int32 readBytes, AsyncProtocolRequest asyncRequest)

Finally I’ve resolved this issue by using the SslProtocols.Tls12 option like below

var cln = new FtpClient(s.Url, s.Port, s.User, s.Password);
cln.EncryptionMode = FtpEncryptionMode.Implicit;
cln.SslProtocols = SslProtocols.Tls12;

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