Xcode beta 6 iOS 8: Simulator not working

Question

I cannot launch the simulator successfully. Once I launch the IOS Simulator this error appears:

\"Unable to boot the IOS Simulator.\"

Answer 1

I saw the same issue when I installed Xcode 6 beta 6, and deleted beta 4 and beta 5. Apparently, deleting the old betas also deleted the iOS Simulator 8 versions! Putting it back from my Trash solved the issue.

Solution: Don't delete old beta software!

Edit: @Flori's solution worked. Was able to delete the old beta software, and after a complete system reboot, it worked again.

Answer 2

I got this issue when moving from Beta 6 to Beta 7. Very frustrating. I could reset content and settings on any of the iOS 8 simulators. None of my iOS 8 simulators were working at all, just a black screen. I restarted my machine during the process, but I am not sure if it did anything. Initially I had only iOS 8 Simulators. I had to remove and reinstall Xcode6Beta7. I did not get the Install More Components the first time I installed it, I am not sure if that was the missing part. I installed the iOS 7 Simulators from Settings->Downloads because my iOS8 ones were not working. After I had reinstalled and relaunched the simulator, I then had a list of iOS 6,7,& 8 simulators. None of the iOS 8 Simulators were working. I was able to launch the iOS7 simulator and then using the device menu change to an iOS 8 Simulator. Some still did not work, I had to remove them and re-add them in the devices screen.

1. Remove XCode6Beta from Applications.
2. Restart Machine (Just in case, this seems to solve some peoples issue completely)
3. Install XCode6Beta.
4. Verify the Install Additional Components ran.
5. Launch Xcode6Beta.
6. Preferences->General->Change Command Line Tools to Xcode 6.0.
7. Restart Xcode.
8. Preferences->Downloads->Download iOS 7 Simulator (If not already downloaded).
9. Run App on iOS 7 Simulator (Or launch iOS Simulator and switch to iOS 7 device)
10. If the iOS 7 Simulator is working, Hardware->Devices->Select an iOS 8 simulator.
11. Delete and recreate any non working iOS 8 Simulators in Window->Devices from Xcode.

Answer 3

Just unset DYLD_INSERT_LIBRARIES environment variable in the /etc/launchd.conf or ~/.launchd.conf file. Which you can edit by sudo vi /etc/launchd.conf command. remove the above flag save it by "ZZ" (captial Z) and reboot the system. It works like a charm.

Answer 4

Is there anything interesting in ~/Library/Logs/CoreSimulator/CoreSimulator.log?

The "Unable to boot the iOS Simulator." error message is almost always because launchd_crashed because DYLD_INSERT_LIBRARIES was set to something not compatible with the iOS Simulator runtime. Do you have any crash logs (eg: launchd_sim crashes) in ~/Library/Logs/DiagnosticReports? If so, check if they show DYLD_INSERT_LIBRARIES being set. If that's the case, your options are to either update to an OS X Yosemite host (which will deal with this issue) or unset DYLD_INSERT_LIBRARIES (likely set in /etc/launchd.conf or ~/.launchd.conf)

Answer 5

Reboot your mac os. its working correctly on xcode 11.3.x and mac os 10.14.6.

Answer 6

Restart your Mac. I just had that exact error after installing Xcode 6 beta 7, literally the only thing I did in response was reboot my Mac and now the iOS 8 simulator is working.

This error is common if you update Xcode without restarting afterwards.