Cannot get reverse proxy for Lync 2013 to work.

Internal is "lyncpool.domain.org" (no override). External is "lyncweb.domain.org".

All SAN certs we are using are from Digicert.

Remote Certificate Subject: CN=lyncweb.domain.org, Issuer: CN=DigiCert SHA2 Secure Server CA, O=DigiCert Inc, C=US. Elapsed Time: 259 ms. Validating the certificate name. The certificate name was validated successfully.

Additional Details

Host name lyncdiscover.domain.org was found in the Certificate Subject Alternative Name entry. Elapsed Time: 1 ms. Testing the certificate date to confirm the certificate is valid. Date validation passed. The certificate hasn't expired.

Additional Details

The certificate is valid. NotBefore = 3/9/2015 12:00:00 AM, NotAfter = 3/16/2016 12:00:00 PM Elapsed Time: 0 ms. Testing HTTP authentication methods for URL https://lyncdiscover.domain.org/Autodiscover/AutodiscoverService.svc/root/user. HTTP authentication test failed.

Additional Details

Exception details: Message: The underlying connection was closed: An unexpected error occurred on a receive. Type: System.Net.WebException Stack trace: at System.Net.HttpWebRequest.GetResponse() at Microsoft.Exchange.Tools.ExRca.Extensions.RcaHttpRequest.GetResponse() Exception details: Message: Unable to read data from the transport connection: An existing connection was forcibly closed by the remote host. Type: System.IO.IOException Stack trace: at System.Net.Sockets.NetworkStream.Read(Byte[] buffer, Int32 offset, Int32 size) at System.Net.FixedSizeReader.ReadPacket(Byte[] buffer, Int32 offset, Int32 count) at System.Net.Security._SslStream.StartFrameHeader(Byte[] buffer, Int32 offset, Int32 count, AsyncProtocolRequest asyncRequest) at System.Net.Security._SslStream.StartReading(Byte[] buffer, Int32 offset, Int32 count, AsyncProtocolRequest asyncRequest) at System.Net.Security._SslStream.ProcessRead(Byte[] buffer, Int32 offset, Int32 count, AsyncProtocolRequest asyncRequest) at System.Net.TlsStream.Read(Byte[] buffer, Int32 offset, Int32 size) at System.Net.PooledStream.Read(Byte[] buffer, Int32 offset, Int32 size) at System.Net.Connection.SyncRead(HttpWebRequest request, Boolean userRetrievedStream, Boolean probeRead) Exception details: Message: An existing connection was forcibly closed by the remote host Type: System.Net.Sockets.SocketException Stack trace: 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) Elapsed Time: 509 ms.