In order to be able to use .NET on OS X, you need to install <b>OpenSSL</b> version <b>1.0.1/1.0.2</b>. There are many ways to install/update your libssl. Using <ahref="http://www.brew.sh">Homebrew</a> is the easiest. You can view the instructions <ahref="http://brewformulas.org/Openssl">here</a> or if you're updating, <ahref="http://apple.stackexchange.com/questions/126830/how-to-upgrade-openssl-in-os-x">on this page</a>.