Ever wondered how to rename your C++ classes that you already use in your project? For example, you have a C++ class called MyAwesomeClass and in your Content Browser you created a Blueprint extending from this class and added some important logic. Now if you rename the C++ parent class and compile, project might open but if you try to open that Blueprint you will see this error.

Simply put, your project is doomed………..Just kidding 😉

So in order to make this work, you need to tell Unreal that there is a new class for this and it should use that instead of the old one. In other words, you need to redirect from Old Class to New One and you do this in DefaultEngine.ini found in Your project/Config folder.

Open DefaultEngine.ini and under [/Script/Engine.Engine] section add the below line:

+ActiveClassRedirects=(OldClassName=”MyAwesomeClass”,NewClassName=”MyNewClass”)

Thats it! Now you can start your project and open that Blueprint without issues. Hope you find this info useful. 🙂