[UE 5.4 iOS] Unknown Cook Failure During Packaging – App Store Also Requires iOS 18 SDK

Hello again!

Thank you for the follow-up. So now, updating UE, and going for a more stable xCode, as yet to yield results. Let’s s try a simple fix, since the updates may have left unused or corrupted data. Test by closing UE, going to your project directory, then deleting Saved and Intermediate folders, and re-open the project to re-generate those files.

If the issue persists after that, we will need the resulting cook trace, as seen in your screenshot: