Xcode 15: Unable to boot the Simulator

Question

I was able to run iOS simulator fine with Xcode 14 and my Mac recently updated the latest version of Xcode which is 15 then I'm no longer able to boot a device from its new simulator.

I did try many different ways collected from many sources but no avail. Here are the few things that I already tried and none of them worked for me:

• Remove all the Xcode caches from Storage either from cli or UI as suggested from here: Flutter: XCode error "Unable to boot the Simulator"
• Try all possible answers from here: https://developer.apple.com/forums/thread/667088
• Follow this article: https://medium.com/@liwp.stephen/my-solution-to-solve-unable-to-boot-the-ios-simulator-39bbb4aad100
• Reinstall Xcode with removing all related files: https://byby.dev/uninstall-xcode#:~:text=Delete%20old%20simulators%20and%20devices,moving%20them%20to%20the%20Trash.
• Downgrade Xcode to v14

BTW here is the full log that I collected as run it via cli:

xcrun simctl boot 39C3D624-968A-49F7-A155-AC9AC1A81B52

Unable to boot the Simulator.
Domain: NSPOSIXErrorDomain
Code: 60
Failure Reason: launchd failed to respond.
User Info: {
    DVTErrorCreationDateKey = "2023-09-26 04:06:49 +0000";
    IDERunOperationFailingWorker = "_IDEInstalliPhoneSimulatorWorker";
    Session = "com.apple.CoreSimulator.SimDevice.AC5CB945-2257-4E8C-AA61-ABC5AC147D84";
}
--
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
--

Event Metadata: com.apple.dt.IDERunOperationWorkerFinished : {
    "device_model" = "iPhone16,1";
    "device_osBuild" = "17.0 (21A328)";
    "device_platform" = "com.apple.platform.iphonesimulator";
    "dvt_coredevice_version" = "348.1";
    "dvt_mobiledevice_version" = "1643.2.4";
    "launchSession_schemeCommand" = Run;
    "launchSession_state" = 1;
    "launchSession_targetArch" = arm64;
    "operation_duration_ms" = 23640;
    "operation_errorCode" = 60;
    "operation_errorDomain" = NSPOSIXErrorDomain;
    "operation_errorWorker" = "_IDEInstalliPhoneSimulatorWorker";
    "operation_name" = IDERunOperationWorkerGroup;
    "param_debugger_attachToExtensions" = 0;
    "param_debugger_attachToXPC" = 1;
    "param_debugger_type" = 3;
    "param_destination_isProxy" = 0;
    "param_destination_platform" = "com.apple.platform.iphonesimulator";
    "param_diag_MainThreadChecker_stopOnIssue" = 0;
    "param_diag_MallocStackLogging_enableDuringAttach" = 0;
    "param_diag_MallocStackLogging_enableForXPC" = 1;
    "param_diag_allowLocationSimulation" = 1;
    "param_diag_checker_tpc_enable" = 1;
    "param_diag_gpu_frameCapture_enable" = 0;
    "param_diag_gpu_shaderValidation_enable" = 0;
    "param_diag_gpu_validation_enable" = 0;
    "param_diag_memoryGraphOnResourceException" = 0;
    "param_diag_queueDebugging_enable" = 1;
    "param_diag_runtimeProfile_generate" = 0;
    "param_diag_sanitizer_asan_enable" = 0;
    "param_diag_sanitizer_tsan_enable" = 0;
    "param_diag_sanitizer_tsan_stopOnIssue" = 0;
    "param_diag_sanitizer_ubsan_stopOnIssue" = 0;
    "param_diag_showNonLocalizedStrings" = 0;
    "param_diag_viewDebugging_enabled" = 1;
    "param_diag_viewDebugging_insertDylibOnLaunch" = 1;
    "param_install_style" = 0;
    "param_launcher_UID" = 2;
    "param_launcher_allowDeviceSensorReplayData" = 0;
    "param_launcher_kind" = 0;
    "param_launcher_style" = 0;
    "param_launcher_substyle" = 0;
    "param_runnable_appExtensionHostRunMode" = 0;
    "param_runnable_productType" = "com.apple.product-type.application";
    "param_structuredConsoleMode" = 1;
    "param_testing_launchedForTesting" = 0;
    "param_testing_suppressSimulatorApp" = 0;
    "param_testing_usingCLI" = 0;
    "sdk_canonicalName" = "iphonesimulator17.0";
    "sdk_osVersion" = "17.0";
    "sdk_variant" = iphonesimulator;
}
--

System Information

macOS Version 13.6 (Build 22G120)
Xcode 15.0 (22265) (Build 15A240d)
Timestamp: 2023-09-26T11:06:49+07:00

I will appreciate any help!

Update on 28th Sep 2023

I just upgraded macOS to the latest version v14 with name (Sonoma)and tried to remove all caches again but still no avail :(

Update on 29th Sep 2023

I also tried to download 3 last iOS versions and interestingly the iOS 15 works for me while none of the 2 others still work.

Update on 16th Nov 2023 (important)

I just re-open the simulator and somehow it suddenly works automatically without doing anything, not sure what has been updated from Apple makes it working. Anyway, this is a good news and I guess Apple might have been aware of the bug and released a fix silently

Answer 1

Here is what worked for me. I am using Xcode Version 15.2

Solution

1. Open System Settings
2. Search Storage >> Developer
3. Delete Xcode caches, project archives and Project Build Data and Indexes

Answer 2

I fixed this by opening Xcode, then Xcode -> Settings -> Platforms. For me iOS 17.0 was not downloaded. After downloading and restarting my computer, the Simulator launched again.

Answer 3

Deleting simulator cache from terminal using rm -r ~/Library/Developer/CoreSimulator/Caches worked for me.

Answer 4

I was facing the same issue I solved it by going to "About this Mac -> Storage -> Manage -> Developer" then by deleting Xcode cache. After that I was able to run my app in simulator.

Answer 5

I had the same issue and error log.

What worked for me was:

1. Go to ~/Library/Developer/CoreSimulator
2. Delete all folders inside.
3. When you now run a simulator, it will say it's not found/missing (since we deleted them).
4. Go to manage run destinations, delete the simulator(in my case it was iPhone 13, iOS 15), click a plus sign, name your new simulator and add a new one. voilá! now you can use the new one for running the app.

Answer 6

Just run this in the terminal:

xcrun simctl shutdown all && xcrun simctl erase all

to reset the iPhone Simulator

Answer 7

I guess you have destroyed the integration of the simulators, but you don’t need to do something with the Xcode cause they are separated totally.

Solution

1. Open your Xcode
2. Manage Run Destination.
3. Find simulators matched your Identifier and delete it.
4. Create a new simulator with the same deviceType and OS Version.
5. Now you are able to boot it with a new identifier.

Answer 8

I had the same case, in my case installing additional old Simulator (it was 16.4 sim runtime) solved the problem. After installing Sim 6.4 and rebooting my mac - voila, suddenly even 17'th Sim started working

Answer 9

Here is what worked for me.

I am using Xcode Version 15.0 (15A240d)

I double checked my registered devices under my apple developer account, I somehow had two different UUID's for the same MacBook Pro, so I checked the same one for my current MacBook and erased the wrong one, I quit Xcode and reopened then simulator worked fine.

Answer 10

I was having extremely long simluator launch times when I updated to Xcode 15 when it released. Downgrade to Xcode 14 helped, but after installing Sonoma on my MacBook Pro M1, unforunatelly, I was not able to use Xcode 14 anymore. And if you are still on macOS Ventura, my advice is to refrain from updating it so far. At least wait for new fixed versions of Xcode 15 to be released.

But if you don't want to downgrade both your macOS and Xcode, then try to use the next steps. They helped me but simulator does not work as smooth as it used to be.

1. Download iOS 16.4 simulator and create simulators with that version.
2. Delete default iOS 17 runtime simulators and recreate them.
3. Delete derived data (Xcode -> Settings-> Locations -> Derived Data (Click the little arrow) -> Delete the folder)

After these steps I was able to run simultators on my MacBook. But I have to say that the launch time of iOS 17 simulator and the apps takes quite more time, and it is still not very responsive and very laggy. You might also see that sometimes it takes forever to attach/install the app, and during this process simulator gets frozen and unresponsive. Restarting Simulator helps.

Didn't face any major issues using iOS 16.4 sim on Sonoma and Xcode 15, so I definetely recommend to use them now as they are smoother, faster and more responsive.

Answer 11

It finally turned out, that in Xcode my User account was logged out, due to a password change I had made on my developer account, and my developer account needed an actualising for the devices after a renewal of my license.

Answer 12

open Activity Monitor and remove Xcodedevice and xcodebuild after this open xcode > developer tools>simulators open simulator

Answer 13

None of these answers works. After several hours, I found that the simulators are listed in the run menu if I create a new project.

My project is created by cmake. So, I found the problem is the Architecture in the project settings:

It should be the 'Standard Architectures (arm64)'. Before, it's 'arm64' only, which is not correct.

After resetting those options to the correct one, the simulators are listed now.

Answer 14

What worked for me:

1. Delete ~/Library/Developer/CoreSimulator folder
2. Attempt to open emulator to get the horizontal menu options at the top left. Click Device -> Erase All Contents and Settings
3. Quit simulator afterwards
4. Reopen simulator

Answer 15

I also got this issue since updating to Xcode 15. When trying to implement Walter's answer above, I found out that adding previous version of simulator (in my case, iOS 15.0) helps to fix the issue, now I can boot my simulator again. Add previous version Simulator by clicking + button on bottom left. No need to restart macbook, can use right away after installing.

Answer 16

I also had this issue (on Xcode 15.1).

For me the problem was the iOS version of the simulator. In the simulators list, each device was listed twice, once with iOS 17.0.1 and once with iOS 17.2. It only worked when selecting a simulator with iOS 17.2.

Answer 17

In my case, I had to update the MacOS ... It was saying that a Mac system update was available but I was ignoring it. After completing the update the "unable to boot simulator." didn't show - instead the iOS emulator turned up.

Try updating your Mac : )