MoreLinq is a library of useful Linq extension methods. It is available on GitHub or by Nuget packages. It can be added directly into LinqPad using ‘f4’ if you have a paid version of LinqPad.
So I had installed, uninstalled, reinstalled SQL Server. For the purpose of one program, I must have my SQL instance running as the default instance (ie: localhost), but after the second install it wasn’t setup right as the default instance.
I found this article on SO which was a life save and told me how to quickly get my named instance accessed as ‘localhost’. Note there can only be one setup this way on your machine.