I have this error using .NET 3.5 on Windows Server 2016 when I try to use TLS 1.2:
Unhandled Exception: System.NotSupportedException: The requested security protocol is not supported.
at System.Net.ServicePointManager.set_SecurityProtocol (SecurityProtocolType value)
TLS 1.2 has been released as a patch to .NET 3.5, according to the articles below. No patch for Windows Server 2016?
Note: Windows update is up to date, and I have servers with Windows Server 2008R2 and 2012 working with TLS 1.2.
Note2: I can't use .NET 4.0, i need to use .NET 3.5.