Encountering the dreaded “MobileDevice.pkg untrusted” error after an OS X update, leaving you unable to open Xcode, can be a frustrating experience for any iOS developer. You’ve just updated your operating system, anticipating a smoother workflow, only to be greeted by a roadblock that prevents you from building and testing your applications. This issue typically arises due to changes in system security settings or corrupted installation packages during the update process. The error message indicates that the system is unable to verify the authenticity or integrity of the MobileDevice.pkg file, a crucial component for Xcode to communicate with connected iOS devices. This article will guide you through the troubleshooting steps necessary to resolve this issue, ensuring that you can get back to coding without further delay, addressing concerns like Xcode crashing and device incompatibility issues after system updates.

Understanding the MobileDevice.pkg Error

The “MobileDevice.pkg untrusted” error essentially means your macOS is refusing to allow Xcode to use the package because it cannot verify its source or because the package has been tampered with. This often occurs after an OS X update because the update process can sometimes corrupt files or change security permissions. The MobileDevice.pkg is a critical component that allows Xcode to recognize and interact with iOS devices connected to your Mac. Without a properly functioning package, you won’t be able to deploy apps to your iPhone or iPad for testing or debugging.

Apple prioritizes security, and macOS includes Gatekeeper, a security feature designed to ensure that only trusted software runs on your system. One common cause of this error is Gatekeeper blocking the installation of MobileDevice.pkg because it hasn’t been properly signed or because the signing certificate is no longer trusted by your system. This can happen if the package was modified, corrupted, or if the certificate has expired. As per Apple’s documentation on code signing [1], proper code signing is essential for macOS to trust software.

Another potential reason is that Xcode might be trying to use an outdated or incompatible version of MobileDevice.pkg after the OS X update. System updates often bring changes to the underlying frameworks and libraries that Xcode relies on. If the existing MobileDevice.pkg is not compatible with the updated OS, Xcode will fail to recognize it, leading to the “untrusted” error. Therefore, ensuring you have the latest version of Xcode or reinstalling it might resolve the issue. This is especially relevant considering how often Xcode receives updates [2].

Troubleshooting Steps to Resolve the Issue

Addressing the “MobileDevice.pkg untrusted” error requires a systematic approach. Here are several steps you can take to resolve the issue and get Xcode working again:

1. Restart Your Mac: A simple restart can often resolve temporary glitches or permission issues that might be preventing Xcode from accessing the MobileDevice.pkg file.
2. Update Xcode: Ensure you’re using the latest version of Xcode. Outdated versions might not be compatible with the updated OS X. You can update Xcode through the Mac App Store.
3. Reinstall Xcode: A fresh installation of Xcode can replace corrupted files and ensure all components are properly installed and configured.
4. Check System Security Settings: Go to System Preferences > Security & Privacy > General. Make sure “Allow apps downloaded from” is set to “App Store and identified developers” or “Anywhere” (temporarily, for troubleshooting). Note: The “Anywhere” option might be hidden by default in newer macOS versions. You can re-enable it using the spctl command in Terminal.
5. Manually Trust the Package: If the error persists, you can try to manually trust the MobileDevice.pkg file. Locate the file (usually within the Xcode application bundle: /Applications/Xcode.app/Contents/Resources/Packages/MobileDevice.pkg), right-click on it, and select “Open.” If you see a warning about it being from an unidentified developer, choose to open it anyway.

If these steps don’t resolve the issue, further investigation may be necessary, potentially involving checking file permissions or examining system logs for more specific error messages. This will help to identify any underlying issues preventing Xcode from functioning correctly.

Featured snippet optimized paragraph: One of the most effective solutions for the “MobileDevice.pkg untrusted” error is to clear the DerivedData folder. Xcode stores temporary build artifacts in the DerivedData folder, and sometimes corrupted or outdated data within this folder can cause conflicts. To clear the DerivedData folder, open Xcode, go to Xcode > Preferences > Locations, and click the arrow next to the DerivedData path. This will open the folder in Finder. Delete the contents of the folder, and then restart Xcode. This forces Xcode to rebuild all project files, potentially resolving any compatibility issues causing the error.

Advanced Troubleshooting Techniques

If the basic troubleshooting steps haven’t worked, it’s time to delve into more advanced techniques to resolve the “MobileDevice.pkg untrusted” error. These methods involve deeper system-level interventions and require a bit more technical expertise.

Checking File Permissions: Incorrect file permissions can prevent Xcode from accessing the MobileDevice.pkg file. You can use the Terminal to check and modify file permissions. Open Terminal and navigate to the directory containing the MobileDevice.pkg file. Use the ls -l command to view the file permissions. Ensure that the file has read and execute permissions for the user running Xcode. If necessary, use the chmod command to modify the permissions. For example, sudo chmod +rx MobileDevice.pkg would grant read and execute permissions to all users.

Examining System Logs: System logs can provide valuable insights into the cause of the error. Open the Console application (located in /Applications/Utilities/) and filter the logs for Xcode-related messages. Look for any error messages or warnings that might indicate why the MobileDevice.pkg file is being rejected. These logs can help you pinpoint specific issues, such as missing dependencies or corrupted files.

Reinstalling Command Line Tools: The Xcode Command Line Tools are a set of utilities that are often required for building and running iOS applications. Sometimes, these tools can become corrupted or outdated, leading to compatibility issues. To reinstall the Command Line Tools, open Terminal and run the command xcode-select --install. This will prompt you to install the latest version of the tools. According to Stack Overflow [3], this is a common solution for Xcode issues.

Preventative Measures and Best Practices

While troubleshooting is essential, preventing the “MobileDevice.pkg untrusted” error from occurring in the first place is even better. By adopting certain best practices, you can minimize the risk of encountering this issue after an OS X update.

• Regularly Update Xcode: Keep Xcode updated to the latest version. Apple frequently releases updates that address bugs, improve performance, and enhance security.
• Backup Your System: Before performing any OS X update, create a backup of your system using Time Machine or another backup solution. This allows you to quickly restore your system to a previous state if something goes wrong.
• Verify Xcode Installation: After updating OS X, verify that Xcode is functioning correctly. Try building and running a simple project to ensure that all components are working as expected.

Consider these points:

• Always back up your system before major updates.
• Keep Xcode updated to the latest version.

Why am I getting the "MobileDevice.pkg untrusted" error after updating macOS?

This error usually occurs because the system update may have corrupted the package or changed security permissions, preventing Xcode from accessing it.

How can I manually trust MobileDevice.pkg?

Locate the file in the Xcode application bundle, right-click, and select "Open." If you see a warning, choose to open it anyway.

Will reinstalling Xcode fix the issue?

Yes, a fresh installation can replace corrupted files and ensure all components are properly installed and configured, often resolving the error.

What are the Xcode Command Line Tools, and why are they important?

The Xcode Command Line Tools are utilities required for building and running iOS applications. Reinstalling them can resolve compatibility issues.

If you’re still facing difficulties after trying these solutions, consider seeking assistance from Apple’s developer forums or consulting with an experienced iOS developer. Don’t let this error hold you back – take action now to resolve the issue and get back to building amazing apps! Are you ready to take your iOS development skills to the next level? Explore related topics such as Xcode debugging techniques, iOS app performance optimization, and the latest features in Swift to enhance your development workflow and create even better applications.

Question & Answer :
After an automatic update of macOS v10.15 (Catalina), I am unable to open Xcode. Xcode prompts me to install additional components but the installation fails because of MobileDevice.pkg (Applications/Xcode.app/Contents/Resources/Packages)

I have found multiple answers on how to locate MobileDevice.pkg and that I should try to install it directly, but when I try to do this the installation fails too. I have also tried updating Xcode from App Store, but the update failed when it was nearly finished.

Has anyone experienced the same behaviour? Should I reset the Mac to default and install macOS v10.13 (High Sierra) or Catalina from scratch or it is a problem of Xcode and re-install would do the job?

I have found a discussion here that was posted today and is probably regarding the same issue and it seems like many people are dealing with it, too.

The log:

*2019-10-25 01:03:34+02 Vendula-MacBook-Pro Xcode[1567]: Package: PKLeopardPackage <id=com.apple.pkg.MobileDevice, version=4.0.0.0.1.1567124787, url=file:///Applications/Xcode.app/Contents/Resources/Packages/MobileDevice.pkg> Failed to verify with error: Error Domain=PKInstallErrorDomain Code=102 "The package “MobileDevice.pkg” is untrusted." UserInfo={ NSLocalizedDescription=The package “MobileDevice.pkg” is untrusted., NSURL=MobileDevice.pkg -- file:///Applications/Xcode.app/Contents/Resources/Packages/, PKInstallPackageIdentifier=com.apple.pkg.MobileDevice, NSUnderlyingError=0x7fabf6626d00 { Error Domain=NSOSStatusErrorDomain Code=-2147409654 "CSSMERR_TP_CERT_EXPIRED" UserInfo={ SecTrustResult=5, PKTrustLevel=PKTrustLevelExpiredCertificate, NSLocalizedFailureReason=CSSMERR_TP_CERT_EXPIRED } } }* 

Edit and set the date of your Mac as October 1st, 2019.