Error opening iOS Simulator with iOS 8 beta version: "Unable to boot the iOS Simulator"

I recently installed the beta of Xcode Version 6 in OS X Mavericks, with which comes the iOS simulator for iOS 8. I've managed to successfully run from Xcode 6 beta on a device with iOS 8 Beta, but opening the simulator always get the same error I have tried to change the hardware version of iPhone 4s, iPhone 5, ... in the simulator and still gives the same error: "Unable to boot the iOS Simulator".

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I'm working with Xcode 5.1 at the same time in Mavericks, any suggestion to solve this? Is a possible problem for run this simulator in Mavericks because is only for OS X 10.10? Thanks.

Solution 1:

After I found some solutions on the web, a combination of procedures worked for me:

Close Xcode and iOS Simulator (and all related applications)
Install (or reinstall) Xcode6-Beta to Applications folder (direct from the .dmg file)
Open Xcode6-Beta and go to Xcode -> Preferences -> Locations -> Command Line Tools and select "Xcode 6.0" (be sure that you've selected the one in Applications folder)
Launch the iOS Simulator and go to iOS Simulator -> Reset Content and Settings...
Close all the applications and restart your mac (I unchecked "Reopen windows...")
Open Xcode6-beta and test the iOS Simulator

Good luck

Solution 2:

I also had this problem and found the solution by doing following steps:

Initially i downloaded Xcode 6 library in Documentation section under the path Xcode --> Preferences --> Downloads and restart my xcode but didn't solve my problem.
Downloaded and installed the iOS 7.1 Simulator under the path Xcode --> Preferences --> Downloads. Restart xcode again and the problem solved.
I am facing same issue again next morning. Unsetting the DYLD_INSERT_LIBRARIES variable solves my problem:-
1. Open terminal and type "sudo vi /etc/launchd.conf" command and press Enter
2. Press I "Insert" mode and change this
```
"setenv DYLD_INSERT_LIBRARIES /usr/lib/libimckit.dylib" 
```
  to this
```
"unsetenv DYLD_INSERT_LIBRARIES /usr/lib/libimckit.dylib" 
```
and press esc to exit from insert mode.
1. Save changes by typing ":wq" Press Enter
2. Reboot your system and problem soloved.

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Prior to that I didn't find any iOS version in front of each listed devices but after installation or by unsetting DYLD_INSERT_LIBRARIES variable I found the same in front of each device.

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