我认为上周发布的最后一次XCode升级似乎打破了我的Xamarin iOS版本。他们失败了：
Failed to locate a valid instance of CoreSimulatorService in the bootstrap. Adding it now.
或者
.../SignInUniversalController_iPhone.storyboard: Error: 2016-07-31 12:11:38.046 ibtoold[23284:2756861] [MT] IBPlatformTool: *** Failed to launch tool with description <IBCocoaTouchPlatformToolDescription: 0x7fce44256b20> System content 1x for IBCocoaTouchFramework-NineOneAndLater w/ default fidelity:
Failed to find or create execution context for description <IBCocoaTouchPlatformToolDescription: 0x7fce44256b20> System content 1x for IBCocoaTouchFramework-NineOneAndLater w/ default fidelity (Failure reason: Software caused connection abort): Failed to find a suitable device for the type SimDeviceType : com.apple.dt.Xcode.IBSimDeviceType.iPad-1x with runtime SimRuntime : 9.3 (13E230) - com.apple.CoreSimulator.SimRuntime.iOS-9-3 (Failure reason: Failed to create SimDeviceSet at path /Users/eric/Library/Developer/Xcode/UserData/IB Support/Simulator Devices. You'll want to check the logs in ~/Library/Logs/CoreSimulator to see why creating the SimDeviceSet failed.): Failed to initialize simulator device set. (Failure reason: Failed to subscribe to notifications from CoreSimulatorService.): Error returned in reply to notification request: Connection invalid (Failure reason: Software caused connection abort)
2016-07-31 12:11:46.096 ibtoold[23284:2756861] [MT] IBPlatformTool: Wrote failed marshalling request diagnostics to path: /var/folders/t9/t9xl93t50ql14mr0lxmmw_2r0000gn/T/IB-agent-diagnostics_2016-07-31_12-11-46_067000
Error: Internal error. Please file a bug at bugreport.apple.com and attach "/var/folders/t9/t9xl93t50ql14mr0lxmmw_2r0000gn/T/IB-agent-diagnostics_2016-07-31_12-11-46_067000".
第一条错误消息中提到的日志似乎不比上面更详细：
Failed to find or create execution context for description <IBCocoaTouchPlatformToolDescription: 0x7fce44256b20> System content 1x for IBCocoaTouchFramework-NineOneAndLater w/ default fidelity (Failure reason: Software caused connection abort): Failed to find a suitable device for the type SimDeviceType : com.apple.dt.Xcode.IBSimDeviceType.iPad-1x with runtime SimRuntime : 9.3 (13E230) - com.apple.CoreSimulator.SimRuntime.iOS-9-3 (Failure reason: Failed to create SimDeviceSet at path /Users/eric/Library/Developer/Xcode/UserData/IB Support/Simulator Devices. You'll want to check the logs in ~/Library/Logs/CoreSimulator to see why creating the SimDeviceSet failed.): Failed to initialize simulator device set. (Failure reason: Failed to subscribe to notifications from CoreSimulatorService.): Error returned in reply to notification request: Connection invalid (Failure reason: Software caused connection abort)
Error Domain=NSPOSIXErrorDomain Code=53 "Software caused connection abort" UserInfo={NSLocalizedDescription=Failed to find or create execution context for description <IBCocoaTouchPlatformToolDescription: 0x7fce44256b20> System content 1x for IBCocoaTouchFramework-NineOneAndLater w/ default fidelity, NSUnderlyingError=0x7fce44152c40 {Error Domain=NSPOSIXErrorDomain Code=53 "Software caused connection abort" UserInfo={NSUnderlyingError=0x7fce441b8150 {Error Domain=NSPOSIXErrorDomain Code=53 "Software caused connection abort" UserInfo={NSLocalizedFailureReason=Failed to subscribe to notifications from CoreSimulatorService., NSLocalizedDescription=Failed to initialize simulator device set., NSUnderlyingError=0x7fce44155b00 {Error Domain=NSPOSIXErrorDomain Code=53 "Software caused connection abort" UserInfo=0x7fce441c31b0 (not displayed)}}}, NSLocalizedFailureReason=Failed to create SimDeviceSet at path /Users/eric/Library/Developer/Xcode/UserData/IB Support/Simulator Devices. You'll want to check the logs in ~/Library/Logs/CoreSimulator to see why creating the SimDeviceSet failed., NSLocalizedDescription=Failed to find a suitable device for the type SimDeviceType : com.apple.dt.Xcode.IBSimDeviceType.iPad-1x with runtime SimRuntime : 9.3 (13E230) - com.apple.CoreSimulator.SimRuntime.iOS-9-3}}}
这是一个iPhone项目，但使用的是通用组件;我注意到，因为上面说的是iPad。
当它失败时，它打开了Storyboard编辑器，它似乎没问题;乍一看似乎没什么可惊讶的。
XCode: Version 7.3.1 (7D1014)
Xamarin: Latest Stable; no updates available
任何见解或想法？谢谢！