In my project, I\'ve include a full \"shared\" folder by link (not copy) that is outside my project folder.
In the .pch file, I have #import \"MyStandardHeader.h
If deleting data and Prefix Header path doesn't work then, try to click on the File (that is not found) in the Project Navigator and uncheck the target under Target Membership in File Inspector. Then deleted the files from Project Project Navigator and add again. This is the only thing that worked for me.