Q:

The type or namespace name 'OpenIdConnect' does not exist in the namespace 'Microsoft.Owin.Security' (are you missing an assembly reference?)

I have added a Microsoft.Owin.Security.OpenIdConnect.dll externally(tried both methods using Package Manager Console and using add reference ) to my ASP.NET MVC Application, but still get the same error.

The type or namespace name 'OpenIdConnect' does not exist in the namespace 'Microsoft.Owin.Security' (are you missing an assembly reference?)

I have attached AccountController.cs, packages.config and references
Any help.

A:

I found the solution from Microsoft site 
https://docs.microsoft.com/en-us/previous-versions/visualstudio/visual-studio-2012/0e92xd7b(v=vs.110)
Possible causes for this error include the following:

An assembly that contains the definition of a type was not referenced in the compilation; use /reference (Import Metadata) to specify the assembly
You passed a variable name to the typeof operator.
You tried to reference an assembly that is not part of your target .NET Framework profile. For more information, see Troubleshooting .NET Framework Targeting Errors.

In my case, the issue is that an assembly that is not part of my target .NET Framework profile.

