iPhone 'Don't Trust This Computer' Error: 5 Ways to Fix

Introduction / Why This Is Needed

When connecting an iPhone or iPad to a new computer, the iOS security system should display a "Trust This Computer?" dialog with a code for confirmation. If this dialog does not appear, or if after tapping "Trust" the device still does not synchronize, a trust error occurs. This blocks creating backups, syncing music/photos, and using iTunes/Finder.

By following this guide, you will restore the connection between your device and computer by resetting outdated or corrupted trust settings and checking key system components.

Requirements / Preparation

Before you begin, ensure:

1. You have an original Apple cable or a certified MFi cable that supports data transfer (not just charging).
2. The latest updates are installed on your computer:
   • macOS: Ventura 13.0+ or Monterey 12.0+.
   • Windows: 10 (version 22H2) or 11.
   • iTunes: 12.12.9.1 or newer (for Windows) or Finder in macOS.
3. The latest version of iOS/iPadOS is active on your iPhone/iPad.
4. You are logged into the computer with an administrator account.

Step-by-Step Instructions

Step 1: Check the Cable and USB Port

Most often, the problem lies in the physical connection.

• Use a cable that is known to work for data transfer (for example, a cable from another device that has synced previously).
• Connect the cable directly to a USB port on the system unit (for a PC) or to a port on the Mac case. Avoid connecting through USB hubs, keyboards, or front panels if they do not provide stable power.
• Try all available USB ports on the computer.

💡 Tip: When connecting to a computer, an iPhone/iPad should display a battery icon in the top status bar or a trust request. If nothing happens, the problem is most likely the cable or port.

Step 2: Restart Devices and Software

A simple restart clears temporary service glitches.

1. On iPhone/iPad: Press and hold the power button and one of the volume buttons until the slider appears. Drag it to power off. After 30 seconds, turn it back on by holding the power button.
2. On the computer: Fully restart macOS or Windows.
3. After the computer boots, close and reopen iTunes (Windows) or Finder (macOS). On macOS, iOS device syncing happens directly in the Finder window under the "General" tab.

Step 3: Update Software

Version incompatibility is a common cause of trust issues.

• On iPhone/iPad: Settings → General → Software Update. Install all available updates.
• On the computer:
  • macOS: System Settings → Software Update.
  • Windows: Windows Settings → Update & Security.
  • iTunes (Windows only): Launch iTunes, go to the menu Help → Check for Updates. Or download the installer from the official Apple website.

Step 4: Reset Trust Settings on iPhone/iPad

This is the key step that clears the cache of all previously trusted computers on the device.

1. On your iPhone/iPad, open Settings.
2. Go to General → Transfer or Reset iPhone → Reset.
3. Select Reset Location & Privacy. Note: This will reset only privacy settings (app permissions, location settings) and computer trust parameters. Your data (photos, apps) will not be deleted.
4. Enter your device passcode if prompted.
5. After the reboot, connect the device to the computer using the cable.
6. The "Trust This Computer?" dialog should appear on the iPhone/iPad screen. Tap "Trust" and enter your device passcode if requested.

⚠️ Important: If the dialog did not appear, repeat Step 1 and Step 2, ensuring the cable and port are functional.

Step 5: Reinstall Drivers (Windows) or Services (macOS)

If the problem persists, the failure may be on the computer's side.

For Windows:

1. Open Control Panel → Programs and Features.
2. Find iTunes in the list and uninstall it.
3. Download the latest version of iTunes from the official Apple website (the installer includes all necessary Apple Mobile Device drivers).
4. Run the installer as an administrator and complete the installation.
5. Restart the computer and connect the iPhone.

For macOS:

1. Open Activity Monitor.
2. Find the processes AppleMobileDeviceService and iTunes (or Music in newer macOS versions).
3. Select each process and click the quit button (X) → Force Quit.
4. Wait 10 seconds and launch Finder (or iTunes, if installed separately) again.
5. Connect the iPhone.

Verification

1. Connect the iPhone/iPad to the computer.
2. The trust dialog should appear and then disappear on the device (if you previously tapped "Trust", it will not show again).
3. In Finder (macOS) or iTunes (Windows), an image of your device should appear in the left sidebar.
4. Try a simple action: create a backup (Back Up Now). If the process completes without errors, the issue is resolved.

Potential Issues

• "Cannot connect to iPhone" error (Windows): Ensure the Apple Mobile Device Service is running. Press Win+R, type services.msc, find the service, set the startup type to "Automatic", and start it.
• Device is recognized as a camera, not an iPhone: The setting Settings → General → Sync with this [Computer] on the iPhone may have "Photos Only" enabled. Disable it.
• Problem persists after all steps: Try connecting the iPhone to a different computer. If the issue is absent on another PC/Mac, the problem lies with the drivers or software on your primary computer (return to Step 5). If the problem exists on all computers, there may be a hardware failure in the Lightning/USB-C port on the iPhone.
• Antivirus or firewall is blocking the connection: Temporarily disable third-party antivirus and the Windows firewall, then try connecting again. If it works, add iTunes and Apple services to the exceptions list.

If none of these solutions helped, the problem may be deeper and related to iOS system files. In this case, as a last resort, consider restoring the device via DFU mode (full reflash). Important: this will erase all data on the iPhone. Before doing this, be sure to make a backup via iCloud if available. Instructions for entering DFU mode and restoring are available in our guide "How to Enter DFU Mode on iPhone and iPad".