When renaming a project, ensure to empty the /bin/ folder within the project for a clean rebuild.
Old DLL’s from previous builds could cause failures in resolving Controller names as 2 or more instances of the same controller would be found under 2 diff namespaces.
Easiest way: Right click solution -> Clean Solution and then Rebuild.
1. Create a ASP.NET Web Project with name – App1 and add a controller.
2. Rebuild this project.
3. Rename project to App2 and all namespaces within.
4. Rebuild this project App2.
5. When making a call to a controller method SomeMethod, the routing complains that it cant resolve the controller name due to 2 instances of the controller – one as App1.SomeMethod and another App2.SomeMethod.
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