As you may know, the payment card industry is moving quickly to adopt TLS 1.2 and get rid of less secure protocols.[1] To this end, Authorizet.Net has turned off TLS.1.2 on its sandbox environment as of April 30, 2017. [2] The curious part about this change is how it impacts the developer world. We have some older projects built using VS2010 (msbuild) and old web deploy projects. Up until April 30, we could build those with .NET 4 and VS2010. So we happily and blindly did that, until May 1. Starting May 1 we started to see those pesky communication disconnection errors. Darn, what is that? Well, that's the TLS 1.2 requirement in sandbox. So we apply the fix and discover that .NET 4 does not have the TLS 1.2 enum SecurityProtocolType. Well, double bummer. When we move on to .NET 4.5.1 to get that SecurityProtocolType.Tls12 we discover that we can no longer use VS2010 msbuild. Why? Because that old VisualStudios can't build .NET 4.5.1. [3] How fun is that? With one change...