My 2nd observation on this problem
What I fear even more is that it looks like some are having local issues. That is one one computer the projects open, while it wont on an other. And the problem may not be visible until you try to package the project…
Made me think about the fact that I followed some tutorial, suggesting that you can save a lot of harddrive space - you can open the options and remove some features that you don’t use… but I guess that you may run into problemes if you want to run or upgrade a project that depends on some of this “optional” stuff? ( (181) SMALLER Unreal Engine Installs! Recover 20+ GB - YouTube
So I suggest that you are a bit careful when removing engine features - maybe I an wrong, I hope so.