Cannot resolve symbol 'nng'

[mo-han]

IDE: JetBrains Rider
installation: via NuGet; Subor.nng.NETCore 1.1.1.1

the installed version is old but the project importing seems fine:

    <Import Project="..\packages\Subor.nng.NETCore.1.1.1.1\build\Subor.nng.NETCore.targets" Condition="Exists('..\packages\Subor.nng.NETCore.1.1.1.1\build\Subor.nng.NETCore.targets')" />

however using nng not work with message: Cannot resolve symbol 'nng'

the project now is set with target framework: .NETFramework v4.6.1
when tried to add reference, error occured:

Rider – Can not add reference
Can not read assembly metadata from '...\nng.dll'.

i used to use NNanomsg, which is flawless (install via nuget, and then just coding with using NNanomsg and everything works as expected).
i'd like to try this one, but tumbled at the first step, what did i miss?

[toebeann]

I haven't used this yet, but it looks to me like you installed the wrong NuGet package:
This is the package you installed: https://www.nuget.org/packages/Subor.nng.NETCore/
This NuGet package is deprecated, and links to a newer package: https://www.nuget.org/packages/nng.NET/
So I would try that.