Razor intellisense error: Feature 'extension method' cannot be used because it is not part of the ISO-2 C# language specification

Question

Goal:

• Use cshtml Razor templates to format data
• Embed cshtml Razor templates in Class Library as Embedded Resources

Answer 1

The key of solving this issue is adding the following tag to your app.config or web.config

Note: In some cases, unloading and reloading the project is required.