First, let me say I've inherited this solution from someone that has left the company...
We generally grab a copy of SolarWinds.InformationService.Contract2.dll from the server after upgrade and reference it from inside our C# application.
The DLL shows up in the References folder.
The issue is, with this version of the DLL (File details say this is 2016.2.0.40) we are getting errors from Visual Studio that "The type or namespace 'SolarWinds' could not be found (are you missing a using directive or an assembly reference?)"
I'm NOT a great coder, but i've made it through a couple of upgrades now and this is the first time this issue has occurred.
Any help appreciated.