Why I can't test the app on my own device even if I signed it with a valid development certificate

Thanks for the post, I would recommend to put the output of the console errors on the body of the message as well will easier to see and warning and errors to that point

The error I see at the last screen may happen when Xcode attempts to install your app onto a physical device, but the app or probably one of its embedded 3rd party frameworks lacks a valid code signature?

If you haven't set up code signing yet, the easiest way to fix this is to let Xcode handle it. Look first at the app team dropdown and make sure everything is valid. Go to the Signing & Capabilities tab and check the box for Automatically manage signing. In the team dropdown, select your Apple Developer account/team.

If your main app is signed but a third-party library or framework is not, Xcode will throw this exact error.

In General, scroll down to Frameworks, Libraries, and Embedded Content. Look at the Embed column for your frameworks. If you have dynamic frameworks like .framework or .xcframework files that are not Apple, make sure they are set to Embed & Sign. Static libraries should be set to "Do Not Embed”.

However the best way is still to looks at the warning and errors to see what framework is causing this.

Albert
  Worldwide Developer Relations.

Thanks for the detailed explanation.

I checked the Signing & Capabilities settings and enabled Automatically manage signing with my Apple Developer account selected. I’ll also inspect the Frameworks, Libraries, and Embedded Content section to make sure the third-party frameworks are set correctly.

I’m going to paste the full console warnings/errors below so it’s easier to identify which framework is causing the issue.

Domain: LaunchExecutableValidationErrorDomain
Code: 1
Recovery Suggestion: Sign the executable with a valid certificate and provisioning profile.
User Info: {
    DVTErrorCreationDateKey = "2026-05-13 02:48:15 +0000";
    IDERunOperationFailingWorker = IDEInstallCoreDeviceWorker;
}
--
Unable to Install “PaperHub”
Domain: MIInstallerErrorDomain
Code: 13
Recovery Suggestion: Failed to verify code signature of /var/installd/Library/Caches/com.apple.mobile.installd.staging/temp.FNhy2z/extracted/IGCSEPastPapers.app : 0xe800801c (No code signature found.)
--
Failed to install the app on the device.
Domain: com.apple.dt.CoreDeviceError
Code: 3002
User Info: {
    NSURL = "file:///Users/raymanguo/Library/Developer/Xcode/DerivedData/IGCSEPastPapers-gienvhafvfdkiqhdqtaqeuklpozw/Build/Products/Debug-iphoneos/IGCSEPastPapers.app";
}
--
Unable to Install “PaperHub”
Domain: IXUserPresentableErrorDomain
Code: 14
Failure Reason: This app cannot be installed because its integrity could not be verified.
Recovery Suggestion: Failed to verify code signature of /var/installd/Library/Caches/com.apple.mobile.installd.staging/temp.FNhy2z/extracted/IGCSEPastPapers.app : 0xe800801c (No code signature found.)
--
Failed to verify code signature of /var/installd/Library/Caches/com.apple.mobile.installd.staging/temp.FNhy2z/extracted/IGCSEPastPapers.app : 0xe800801c (No code signature found.)
Domain: MIInstallerErrorDomain
Code: 13
User Info: {
    FunctionName = "+[MICodeSigningVerifier _validateSignatureAndCopyInfoForURL:withOptions:error:]";
    LegacyErrorString = ApplicationVerificationFailed;
    LibMISErrorNumber = "-402620388";
    SourceFileLine = 80;
}
--

Event Metadata: com.apple.dt.IDERunOperationWorkerFinished : {
    "device_identifier" = "00008142-001419392E11401C";
    "device_isCoreDevice" = 1;
    "device_model" = "iPad17,1";
    "device_osBuild" = "26.4.2 (23E261)";
    "device_osBuild_monotonic" = 2304026100;
    "device_os_variant" = 1;
    "device_platform" = "com.apple.platform.iphoneos";
    "device_platform_family" = 2;
    "device_reality" = 1;
    "device_thinningType" = "iPad17,1-A";
    "device_transport" = 0;
    "launchSession_schemeCommand" = Run;
    "launchSession_schemeCommand_enum" = 1;
    "launchSession_targetArch" = arm64;
    "launchSession_targetArch_enum" = 6;
    "operation_duration_ms" = 537;
    "operation_errorCode" = 1;
    "operation_errorDomain" = LaunchExecutableValidationErrorDomain;
    "operation_errorWorker" = IDEInstallCoreDeviceWorker;
    "operation_error_reportable" = 0;
    "operation_name" = IDERunOperationWorkerGroup;
    "param_consoleMode" = 1;
    "param_debugger_attachToExtensions" = 0;
    "param_debugger_attachToXPC" = 1;
    "param_debugger_type" = 3;
    "param_destination_isProxy" = 0;
    "param_destination_platform" = "com.apple.platform.iphoneos";
    "param_diag_MTE_enable" = 0;
    "param_diag_MainThreadChecker_stopOnIssue" = 0;
    "param_diag_MallocStackLogging_enableDuringAttach" = 0;
    "param_diag_MallocStackLogging_enableForXPC" = 1;
    "param_diag_allowLocationSimulation" = 1;
    "param_diag_checker_mtc_enable" = 1;
    "param_diag_checker_tpc_enable" = 1;
    "param_diag_gpu_frameCapture_enable" = 0;
    "param_diag_gpu_shaderValidation_enable" = 0;
    "param_diag_gpu_validation_enable" = 0;
    "param_diag_guardMalloc_enable" = 0;
    "param_diag_memoryGraphOnResourceException" = 0;
    "param_diag_queueDebugging_enable" = 1;
    "param_diag_runtimeProfile_generate" = 0;
    "param_diag_sanitizer_asan_enable" = 0;
    "param_diag_sanitizer_tsan_enable" = 0;
    "param_diag_sanitizer_tsan_stopOnIssue" = 0;
    "param_diag_sanitizer_ubsan_enable" = 0;
    "param_diag_sanitizer_ubsan_stopOnIssue" = 0;
    "param_diag_showNonLocalizedStrings" = 0;
    "param_diag_viewDebugging_enabled" = 1;
    "param_diag_viewDebugging_insertDylibOnLaunch" = 1;
    "param_install_style" = 2;
    "param_launcher_UID" = 2;
    "param_launcher_allowDeviceSensorReplayData" = 0;
    "param_launcher_kind" = 0;
    "param_launcher_style" = 99;
    "param_launcher_substyle" = 0;
    "param_lldbVersion_component_idx_1" = 0;
    "param_lldbVersion_monotonic" = 210000160012;
    "param_runnable_appExtensionHostRunMode" = 0;
    "param_runnable_productType" = "com.apple.product-type.application";
    "param_testing_launchedForTesting" = 0;
    "param_testing_suppressSimulatorApp" = 0;
    "param_testing_usingCLI" = 0;
    "sdk_canonicalName" = "iphoneos26.4";
    "sdk_osVersion" = "26.4";
    "sdk_platformID" = 2;
    "sdk_variant" = iphoneos;
    "sdk_version_monotonic" = 2304025200;
}
--


System Information

macOS Version 26.5 (Build 25F71)
Xcode 26.4.1 (24909.0.3) (Build 17E202)
Timestamp: 2026-05-13T10:48:15+08:00

Thanks for providing this, my first thought when I saw is is the path /var/installd/Library/Caches looks really weird to me and ensure that the value for Debug is set to Apple Development and not "None" as well as all configuration for that build. is valid and you do not have anything hardcoded. your build settings might be explicitly telling Xcode not to sign the app.

Trust the Developer on your Device as well? Have you tried the simulator? I do believe is the device not being setup well?

However posting that error will help many people figure it out what could be wrong as I never seen that before personally. Have you tried instead of a build machine to use Xcode only? As com.apple.dt.IDERunOperationWorkerFinished is something that should not be on Xcode? How are you building the app?

Albert
  Worldwide Developer Relations.

Thanks a lot — you were right to point me toward the build settings.

I found that CODE_SIGNING_ALLOWED was actually set to NO. After changing it to YES, the app installed successfully on the physical device.

Really appreciate the help.