Unable to boot the IOS simulator

Question

When I'm running project build is succeeded, but simulator is not loading saying message "Unable to boot the simulator". Im only able to test in real device.

Please help me .

Thank you....

Answer 1

It's hard to say what exactly is the problem. But there are only 3 possibilities that I can think of:

1. the iOS image that simulator tries to load is corrupted/not downloaded properly.
2. You are using a CPU architecture that is not supported by iOS simulator.
3. File permission issues. You are running XCode from a location or by a user that doesn't give you enough access to load the iOS images.

Answer 2

Had exactly the same problem at the time of the original post. Everything was working fine a day before, running OS X 10.11.6, with both XCode 7.1.1 & XCode 8 installations. Tried everything from rebooting, cleaning, etc. to reinstalling XCode without any success.

In my case, permissions for "private/tmp" mysteriously changed.

1. check .../Library/Logs/DiagnosticReports for crashes of "launchd_sim" and possible hints
2. open terminal and run "sudo /usr/libexec/repair_packages --verify --standard-pkgs /". If it says something about "private/tmp", you're likely having the same issue.
3. either try to repair the permissions yourself ( it's a pain with El Capitan ), or run a OS X update if you haven't. The later did the trick for me...

Hope it solves your problem as well.

Answer 3

这是一个奇怪的问题，但更新到 macOS Sierra 似乎可以解决它。

Answer 4

下载最新的模拟器（Preference - Components），安装好后，再次运行。