Accessing VB.net class from .cshtml file

I have a VS solution with 2 projects. One in VB and the other one in C#. The C# project is my web project and the VB contains the logic.

I currently try to access a VB.NET class in the VB project from the c# web project.

The problem is, that I can't do. It keeps saying, the the namespace or assemlby is missing.

I already added the VB project as a reference to the C# project and I can access the VB class from a C# class. But not from a .cshtml file. It sayes (translated): The type- or namespacename "TheClassIWantToUse" was not found (possibly a using-annotation or a assembly is missing)

What I have to do?

Do I have to add a namespace. I tryed to "wrap" the class I want to use into a namespace, but that didn't work for me. Did I missed something?