Error: The type exists in both directories

Question

In a MVC2 project I moved a file from App_code to Content folder and compiled it. Then move it back again to App_Code and then changed its Build Action to \"Compile\". Now I

Answer 1

My issue was with different version of DevExpress.
Deleting all contents from bin and obj folders made my website run again...

Reference: https://www.devexpress.com/Support/Center/Question/Details/KA18674