Bad references of files in a XCode project

Question

I'm trying to copy/paste my XCode project in an other folder of my Mac but when I open it in the new folder, all the files are in red like there was not in the project. But the files are in the good arborescence of the project.

I already try to delete them and add them but it still doesn't work :/

Answer 1

You have only the reference now! delete those files and drag them to the project again, while doing so, please select the "copy items to destination folder" option