I'm using Visual Studio 2017 and trying to add a new reference between two projects, however I get following error when I click on "Add Reference..."
Cannot find an instance of the Microsoft.VisualStudio.Shell.Interop.IVsReferenceManager service.
The first project is Asp.Net Core, and the second project is a .NET Core Class Library.
I had this issue with all my projects after installing another version of Visual Studio.
I fixed it by following 宝宝徐's advice here, namely running the following commands in command prompt:
CD C:\Program Files\Microsoft Visual Studio\2017\Community\Common7\IDE\PublicAssemblies
gacutil -i Microsoft.VisualStudio.Shell.Interop.11.0.dll
I found out that on my machine (Windows 10 x64), apparently gacutil is no longer bundled with new versions of Windows, so retrieved it from a previously installed Microsoft Windows SDK which I found at C:\Program Files (x86)\Microsoft SDKs\Windows\v7.0A\Bin, although I think you may need to install it first. There are some thoughts here about finding gacutil on Windows 10.
After this, I was able to add references to projects again.
Hope that helps someone.
=>Run the "developer Command Prompt as administrator"
=>Goto the path "CD C:\Program Files (x86)\Microsoft Visual Studio\20XX\Enterprise\Common7\IDE\PublicAssemblies"
N.B : 20XX=2017,2019 etc and Enterprise=Enterprise,Community etc
=>Run gacutil -i Microsoft.VisualStudio.Shell.Interop.11.0.dll
=>Restart your pc
I had similar error after migrating Visual Studio 2017 project to Visual Studio 2019. In my case I used Visual Studio Installer and under features there was Visual Studio SDK which was unchecked. After installing that, problem gone.
In my case it was just easier to go to NuGet and Browse for Microsoft.VisualStudio.Shell.Interop.11.0 then add.