What must I do to establish a secure channel for SSL/TLS?

See more:

C#

.NETCF

REST

WinCE

sockets

SSL

TLS

From a C# app (Compact Framework, Windows CE app), I am trying to call a REST method on a server running on our internal network, but the call fails with "Could not establish secure channel for SSL/TLS ...System.Net.Sockets.SocketException: An existing connection was forcibly closed by the remote host"

What must I do to establish a secure channel for SSL/TLS?

Note: The same code running from a "test" app on my PC returns a different, albeit similar, err msg: "Could not establish trust relationship for the SSL/TLS secure channel"

This is the "Readers Digest" version of the question I pos[t]ed here: http://stackoverflow.com/questions/27642714/how-can-i-establish-a-secure-channel-for-ssl-tls-from-a-handheld-device[^]