Here are more details about my machine: MacBook Pro, 14-inch, Nov 2023 Apple M3 Pro 18 GB 15.4.1 (24E263)

Thank you for quick response! I am able to build and run the app on a physical device which is good, but obviously not ideal for making UI changes quickly. I cannot launch the Simulator app manually. I will follow the instructions and provide the information as soon as possible.

I have replicated the issue and run the sysdianosis to gather system information. Attached is the screenshot of Xcode showing the error in the Preview panel. Here is the open point list: Install Preview profile Reproduce issue in Xcode and take a screenshot Run sysdiagnose while running Xcode with issue TODO Send sysdiagnose results file to Apple support I can't upload the report due to an error on this web page so I will try again later

I am unable to upload the full report, so here is the text copied from Xcode: Xcode Report Text

Update: the issue appears to be with iOS 18.4.1 Simulator Runtime. I am able to preview a simulated iOS device running iOS 18.3.1 so the issue appears to be with iOS 18.4.

I can certainly give it a try. I will install the beta release and let you know the results.

I have tried Xcode 16.4 beta but the simulator failure is still happening for iOS versions greater than 18.3.1. I have tried to preview SwiftUI views using iOS simulator runtimes 18.4 and 18.5 but they both fail with the same error message in the original post.

@Matthew3 I am now running VS Code with the Flutter extension. However, the simulator failure existed before I started developing with Flutter.

Update: I installed Xcode 26 beta 4 and updated my MacBook to MacOS 15.6, and now the iOS 26 simulator works. However, iOS 18.4, 18.5, and 18.6 will not launch in the Simulator app and throws the same error listed previously.