The "Reuse TLS/SSL session ID for data connection" is enabled by default (both in GUI and the .NET assembly). You do not need to code anything to turn it on.
If you have still problems, please attach a full session log file (using the latest version of WinSCP).
Forgive me at the start if the post is in the wrong section or else but it's my first time using the forum!
I'm having a problem on the library in a nutshell, I'm missing a setting!
From the client I have no problem with the checkbox: "Reuse TSL/SSL session ID for data connections" under the "Advance Site Settings", I solve the problem.. but from code I can not find the corresponding action!
So I'm asking you how can I set the same parameter shown in the attachment from code?