Blogical SFTP Adapter Issue - Send Port remains in Active state

Hi,

Please advice.

Send Port remains in 'Active' state in BizTalk admin console.

This was working fine before...Suddenly getting this error.

Following is StackTrace:

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Method: Blogical.Shared.Adapters.Sftp.SftpTransmitterEndpoint.ProcessMessage
Error: [SftpTransmitterEndpoint] Unable to transmit file biztalk/EDI/inbound/PO850.edi.
Inner Exception:
Unable write file to biztalk/EDI/inbound/PO850.edi
Unable to connect to Sftp host [SFTPSite.SMB.COM]. Changing any Send Port Transport properties might require the host to be restarted, as the connection pool might still have connections

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Information:
Type: Blogical.Shared.Adapters.Sftp.SftpException
Target: Microsoft.BizTalk.Message.Interop.IBaseMessage ProcessMessageInternal(Microsoft.BizTalk.Message.Interop.IBaseMessage, Blogical.Shared.Adapters.Sftp.ISftp)
Message: [SftpTransmitterEndpoint] Unable to transmit file biztalk/EDI/inbound/PO850.edi.
Inner Exception:
Unable write file to biztalk/EDI/inbound/PO850.edi
Unable to connect to Sftp host [SFTPSite.SMB.COM]. Changing any Send Port Transport properties might require the host to be restarted, as the connection pool might still have connections
Stacktrace:
   at Blogical.Shared.Adapters.Sftp.SftpTransmitterEndpoint.ProcessMessageInternal(IBaseMessage message, ISftp sftp)
   at Blogical.Shared.Adapters.Sftp.SftpTransmitterEndpoint.ProcessMessage(IBaseMessage message)

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Type: Blogical.Shared.Adapters.Sftp.SftpException
Target: Void Put(System.IO.Stream, System.String)
Message: Unable write file to biztalk/EDI/inbound/PO850.edi
Stacktrace:
   at Blogical.Shared.Adapters.Sftp.SharpSsh.Sftp.Put(Stream memStream, String destination)
   at Blogical.Shared.Adapters.Sftp.SftpTransmitterEndpoint.ProcessMessageInternal(IBaseMessage message, ISftp sftp)

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Type: System.Exception
Target: Void connect(Boolean)
Message: Unable to connect to Sftp host [SFTPSite.SMB.COM]
Stacktrace:
   at Blogical.Shared.Adapters.Sftp.SharpSsh.Sftp.connect(Boolean force)
   at Blogical.Shared.Adapters.Sftp.SharpSsh.Sftp.reConnect()
   at Blogical.Shared.Adapters.Sftp.SharpSsh.Sftp.Put(Stream memStream, String destination)

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Type: Tamir.SharpSsh.jsch.JSchException
Target: Void connect(Int32)
Message: invalid server's version String
Stacktrace:
   at Tamir.SharpSsh.jsch.Session.connect(Int32 connectTimeout)
   at Tamir.SharpSsh.SshBase.ConnectSession(Int32 tcpPort)
   at Tamir.SharpSsh.SshBase.Connect(Int32 tcpPort)
   at Blogical.Shared.Adapters.Sftp.SharpSsh.Sftp.connect(Boolean force)

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