WebRequest fails over TLS 1.1 / 1.2 for Windows Server 2008

Question

I\"m running a .net 4.5 application which makes secure outbound requests to an external server supporting only TLS 1.1 and TLS 1.2. All goes fine when i run the application from

Answer 1

I found an indirect proof for you.

SecurityProtocolType Enumeration

Specifies the security protocols that are supported by the Schannel security package.

Support for SSL/TLS protocols on Windows

Now let’s come to the point, on Windows the support for SSL/TLS protocols is tied to the SCHANNEL component. So, if a specific OS version doesn’t support a SSL/TLS version, this means it remains unsupported.

Secure channel compatibility support with SSL and TLS

Answer 2

because Windows Server 2008 does not support TLS 1.1 and TLS 1.2 the WebRequest also fails.

Yes, this is the case.

Any documentation to point me to?

From https://support.microsoft.com/en-us/kb/245030:

Windows Server 2008 supports the following protocols:
 SSL 2.0
 SSL 3.0
 TLS 1.0

Windows Server 2008 R2 and Windows 7 support the following protocols:
 SSL 2.0
 SSL 3.0
 TLS 1.0
 TLS 1.1
 TLS 1.2