Unhandled error when handling request from client

I am currently running server version 3.3.19
I have around 60 deployment targets on my Octopus server all running version 3.3.22 of the octopus client and using the Polling method to hit the management server.

Until today I have had no issue creating new octopus deployment targets, if I remove an Octopus deployment target on one of my machines then re-add it, I get the following error in the server log:
2016-10-06 06:16:52.5629 113 INFO listen://[::]:10943/ 113 Unhandled error when handling request from client: [::ffff:##.##.##.##]:62352
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 Halibut.Transport.SecureListener.ExecuteRequest(TcpClient client) in y:\work\7ab39c94136bc5c6\source\Halibut\Transport\SecureListener.cs:line 104

And the following error on the client:
Connecting to server: http://##.##.##.##:10943
Error: Unable to connect to the Octopus Deploy server. See the inner exception for details.
System.Exception: Unable to connect to the Octopus Deploy server. See the inner exception for details. —> System.Net.WebException: The underlying connection was closed: An unexpected error occurred on a receive. —> System.IO.IOException: Unable to read data from the transport connection: An existing connection was forcibly closed by the remote host. —> System.Net.Sockets.SocketException: An existing connection was forcibly closed by the remote host
at System.Net.Sockets.Socket.Receive(Byte[] buffer, Int32 offset, Int32 size, SocketFlags socketFlags)
at System.Net.Sockets.NetworkStream.Read(Byte[] buffer, Int32 offset, Int32 size)
— End of inner exception stack trace —
at System.Net.Sockets.NetworkStream.Read(Byte[] buffer, Int32 offset, Int32 size)
at System.Net.Connection.SyncRead(HttpWebRequest request, Boolean userRetrievedStream, Boolean probeRead)
— End of inner exception stack trace —
at System.Net.HttpWebRequest.GetResponse()
at Octopus.Client.OctopusClient.DispatchRequest[TResponseResource](OctopusRequest request, Boolean readResponse) in Y:\Work\refs\tags\3.3.22\source\Octopus.Client\OctopusClient.cs:line 491
at Octopus.Client.OctopusClient.Get[TResource](String path, Object pathParameters) in Y:\Work\refs\tags\3.3.22\source\Octopus.Client\OctopusClient.cs:line 83
at Octopus.Client.OctopusClient.EstablishSession() in Y:\Work\refs\tags\3.3.22\source\Octopus.Client\OctopusClient.cs:line 304
— End of inner exception stack trace —
at Octopus.Client.OctopusClient.EstablishSession() in Y:\Work\refs\tags\3.3.22\source\Octopus.Client\OctopusClient.cs:line 339
at System.Lazy1.CreateValue() at System.Lazy1.LazyInitValue()
at Octopus.Manager.Tentacle.TentacleConfiguration.SetupWizard.TentacleSetupWizardModel.VerifyCredentials(ILog logger) in Y:\Work\refs\tags\3.3.22\source\Octopus.Manager.Tentacle\TentacleConfiguration\SetupWizard\TentacleSetupWizardModel.cs:line 298

What could be the cause of this issue?

Hi Brad,

Thanks for getting in touch! Very recently Windows Server 2008 released a patch that disabled TLS 1.0. It causes the error you are seeing.
We have written a troubleshooting and solution guide: http://docs.octopus.com/display/OD/Troubleshooting+Schannel+and+TLS

Please let me know if this does not resolve the issue for you.

Vanessa

Hi Vanessa,

That’d be great if we were using Windows Server 2008, I guess I should of specified in my question what my server version was. Anyway we using Windows Server 2012.

The solution our network guy came up with was to just open all the ports on our production servers so now it works! Thanks for the help anyway,

Cheers,
Brad