Hi,
The App_Code is designed for website project. If you add class to App_Code folder in your ASP.NET web application, this class is treated as "Content" instead of "Compile" by default.
In your case, you try to rename this App_Code folder or create a Class library to compile this class to dll and then add reference to it.
If this doesn’t help you, please feel free to let me know.
I hope this helps.
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