Xamarin.iOS application failed to run on simulator(Probably after last Xamarin.iOS update)

Question

iOS apps are not starting in iPhone simulator(iPhone 5 - iOS 10.0 used ). There are errors from logs CoreSimulator.log:

mlaunch[1482] <Error>: Error Domain=FBSOpenApplicationServiceErrorDomain Code=1 "The request to open "com.xamarin.acquaint-native" failed." UserInfo={NSLocalizedDescription=The request to open "com.xamarin.acquaint-native" failed., BSErrorCodeDescription=RequestDenied, NSUnderlyingError=0x7fe15ceb7540 {Error Domain=FBSOpenApplicationErrorDomain Code=1 "(null)" UserInfo={BSErrorCodeDescription=Unspecified}}, NSLocalizedFailureReason=The request was denied by service delegate (SBMainWorkspace) for reason: Unspecified.}

System.log(Debug mode from Xamarin Studio or VS 2015):

Nov 10 00:00:01 macmini CoreSimulatorBridge[5136]: Requesting launch of com.companyname.FasterNotesMobile.iOS with options: {
        arguments =     (
            "-monodevelop-port",
            51746
        );
        environment =     {
            "DYLD_INSERT_LIBRARIES" = "/Library/Frameworks/Xamarin.iOS.framework/Versions/Current/lib/monotouch-fixes.dylib";
        };
    }
Nov 10 00:00:01 macmini CoreSimulatorBridge[5136]: [Common] [FBSSystemService][0xe350] Sending request to open "com.companyname.FasterNotesMobile.iOS"
Nov 10 00:00:01 macmini com.apple.CoreSimulator.SimDevice.3D2EDEEE-4261-4B99-9B31-971D08B0124E.launchd_sim[5110] (UIKitApplication:com.companyname.FasterNotesMobile.iOS[0xe451][5510]): Program specified by service does not contain one of the requested architectures: 
Nov 10 00:00:01 macmini SpringBoard[5127]: [Common] Unable to get pid for 'UIKitApplication:com.companyname.FasterNotesMobile.iOS[0xe451]': No such process (err 3)
Nov 10 00:00:01 macmini SpringBoard[5127]: [Common] Bootstrapping failed for <FBApplicationProcess: 0x7a79b830; com.companyname.FasterNotesMobile.iOS; pid: -1>
Nov 10 00:00:01 macmini CoreSimulatorBridge[5136]: [Common] [FBSSystemService][0xe350] Error handling open request for com.companyname.FasterNotesMobile.iOS: <NSError: 0x7b871a30; domain: FBSOpenApplicationServiceErrorDomain; code: 1 (RequestDenied); reason: "The request was denied by service delegate (SBMainWorkspace) for reason: Unspecified."> {
        description = "The request to open "com.companyname.FasterNotesMobile.iOS" failed.";
        failureReason = "The request was denied by service delegate (SBMainWorkspace) for reason: Unspecified.";
        underlyingError = <NSError: 0x7b871c10; domain: FBSOpenApplicationErrorDomain; code: 1 (Unspecified)> {
            description = "The operation couldn’t be completed. (FBSOpenApplicationErrorDomain error 1.)";
        };
    }
Nov 10 00:00:01 macmini CoreSimulatorBridge[5136]: Error Launching: Error Domain=FBSOpenApplicationServiceErrorDomain Code=1 "The request to open "com.companyname.FasterNotesMobile.iOS" failed." UserInfo={NSLocalizedFailureReason=The request was denied by service delegate (SBMainWorkspace) for reason: Unspecified., NSLocalizedDescription=The request to open "com.companyname.FasterNotesMobile.iOS" failed., BSErrorCodeDescription=RequestDenied, NSUnderlyingError=0x7b871c10 {Error Domain=FBSOpenApplicationErrorDomain Code=1 "(null)" UserInfo={BSErrorCodeDescription=Unspecified}}}
Nov 10 00:00:01 macmini com.apple.CoreSimulator.SimDevice.3D2EDEEE-4261-4B99-9B31-971D08B0124E.launchd_sim[5110] (UIKitApplication:com.companyname.FasterNotesMobile.iOS[0xea1e][5511]): Program specified by service does not contain one of the requested architectures: 
Nov 10 00:00:01 macmini SpringBoard[5127]: [Common] Unable to get pid for 'UIKitApplication:com.companyname.FasterNotesMobile.iOS[0xea1e]': No such process (err 3)
Nov 10 00:00:01 macmini SpringBoard[5127]: [Common] Bootstrapping failed for <FBApplicationProcess: 0x80a24f00; com.companyname.FasterNotesMobile.iOS; pid: -1>
Nov 10 00:00:05 macmini calaccessd[5164]: 25534103: Beginning CalScheduledTaskCacheTrimAndExtendAndUpdateOverdue
Nov 10 00:00:05 macmini calaccessd[5164]: 25534103: ScheduledTaskCache last saved 499237200
Nov 10 00:00:05 macmini calaccessd[5164]: 25534103: today is EKCalendarDate <0x7c17e740> { date = Thursday, November 10, 2016 at 12:00:00 AM CST }, comparisonResult is -1
Nov 10 00:00:05 macmini calaccessd[5164]: 25534103: Updating overdue with today 500450400.000000

The log above are for acquaint pre build application. I tried several other application, the same story. It used to work fine. I am using latest Xamarin iOS SDK update(that maybe the issue)

Answer 1

Got same problem with a new project and the latest Xamarin. To fix it I had to change "Supported architectures" to "i386" in the project options. The default was "x86_64".