How do I fix: The handshake failed due to an unexpected packet format?

Question

I am connecting from Windows Server 2008 R2 to a Linux FTP Server running vsFTPd 2.0.7. I am connecting via SSL.

Here is the line of code it is failing on:

sslStream = new SslStream(stream, false, CertificateValidation);

Here is the log: 220 (vsFTPd 2.0.7) AUTH SSL 234 Proceed with negotiation.

I receive the following error:

System.IO.IOException: The handshake failed due to an unexpected packet format. at System.Net.Security.SslState.StartReadFrame(Byte[] buffer, Int32 readBytes, AsyncProtocolRequest asyncRequest) at System.Net.Security.SslState.StartReceiveBlob(Byte[] buffer, AsyncProtocolRequest asyncRequest) at System.Net.Security.SslState.ForceAuthentication(Boolean receiveFirst, Byte[] buffer, AsyncProtocolRequest asyncRequest) at System.Net.Security.SslState.ProcessAuthentication(LazyAsyncResult lazyResult) at KellermanSoftware.NetFtpLibrary.ProxySocket.InitSsl() at KellermanSoftware.NetFtpLibrary.FTP.Connect(Boolean implicitConnection)

Answer 1

From my google search, it appears that this is a common problem for vsftpd.
http://www.question-defense.com/2010/02/04/vsftpd-error-gnutls-error-9-a-tls-packet-with-unexpected-length-was-received

You might check out that article for hints to a solution

update
Something else to check out is: http://ftps.codeplex.com/Thread/View.aspx?ThreadId=63605