Highcharts for ASP.NET MVC has a server-side, which include a DLL library, and a client-side that is a set of Javascript code files. Both sides are required to set up a chart.
There are two methods to add the server-side (DLL library) to your project:
1. First method Download dll files from here and add proper reference to your project.
2. Second method Use NuGet to download Highsoft's packages.
Use the search bar to look for the official Highsoft’s library. Type “Highsoft.Higcharts” or “Highsoft.Highstock”.