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

Hello, thank you for your previous response!

I’ve followed your instructions and upgraded my project from Unreal Engine 5.4 to 5.6.

To isolate the issue, I’ve removed all custom and Marketplace plugins from the project. My goal is simply to test remote packaging for iOS using a clean setup.

In addition, I’ve downgraded Xcode to version 16.1 to make sure it stays within a more stable compatibility range. However, the same error still persists.

You can find the latest log here:
C:\Users\User\AppData\Roaming\Unreal Engine\AutomationTool\Logs\C+Program+Files+Epic+Games+UE_5.6\Log.txt
(I’ve attached the full log file as well.)
Log.txt (129.5 KB)

Here is a screenshot showing the error during packaging:

If needed, I can also provide additional logs like:

  • UBA-Marunouchi-IOS-Shipping_2_Remote.txt

Let me know what would be most helpful to troubleshoot this issue.

Thanks again for your support!