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When running on older iOS Simulator, error "Failed to start launchd_sim: could not bind to session, launchd_sim may have crashed or quit responding"


I'm running Xcode 12.2 (12B45b) on my M1 MacBook Pro. Whenever I try to run the simulator on an older iOS, for example:

iPhone 11 Pro (13.0)

It doesn't work. Xcode pops up this error:

Failed to start launchd_sim...

When I press on Details, a screen pops up showing:

Details

Failed to start launchd_sim: could not bind to session, launchd_sim may have crashed or quit responding
Domain: com.apple.SimLaunchHostService.RequestError
Code: 4
--


System Information

macOS Version 11.0 (Build 20A2411)
Xcode 12.2 (17535) (Build 12B45b)
Timestamp: 2020-12-06T12:41:11-08:00

However, If I run a newer iOS like 14.2, it works perfectly. This was the runtime that came preinstalled with Xcode.

Working perfectly

I looked at this question, iOS Simulator is Crashing on startup, but the answer is almost useless. Some other people have had the same problem on the Dev Forums, but no one has a solution yet either.

Edit: It seems there is a mention of this on the release notes for Xcode 12.2:

Simulator runtimes for iOS 13, tvOS 13, and watchOS 6 and earlier don’t work on the Developer Transition Kit. Preferences offers these runtimes for download, but creating a simulated device from one of these runtimes fails, claiming the runtime is unavailable. Other Macs with Apple silicon support a limited set of older simulator runtimes for iOS and tvOS. (66115743, 70472441) (FB8157217)


Solution

  • Seems like it's fixed in Big Sur 11.0.1!

    Running on iOS 13 simulator

    "About this mac" description

    As a side note, updating your M1 Mac is really fast! It literally took 20 minutes.