If you accidentally tapped “Trust” on a public or shared computer, you may worry that your iPhone’s data is now vulnerable. Fortunately, Apple gives you a way to untrust all previously trusted computers directly from your iPhone. While you can’t untrust a specific machine individually, you can reset all trusted devices at once using a quick privacy setting.
In this guide, you’ll learn how to untrust all computers, what actually happens when you trust a computer, and how to stay safe when using your iPhone with public or unfamiliar machines.
🔐 What Happens When You Tap “Trust” on a Computer?
When you connect your iPhone to a computer and tap “Trust”, the iPhone authorizes that computer to:
- Access your device’s files and settings
- Back up and restore your iPhone
- Sync content via Finder or iTunes
- Use developer tools or device diagnostics
Once trusted, that computer will not prompt for approval again until you reset your trust settings or erase the device.
⚠️ If you trust a public, work, or unknown computer, that system may retain partial access to your data if connected again—even without your immediate permission.
✅ How to Untrust All Computers From Your iPhone
Apple doesn’t allow you to “untrust” one specific computer, but you can clear all trusted computers at once by resetting your iPhone’s location and privacy settings.
📲 Step-by-Step: Reset Location & Privacy
- Open the Settings app on your iPhone
- Tap General
- Scroll down and tap Transfer or Reset iPhone
- Tap Reset
- Select Reset Location & Privacy
- Enter your passcode when prompted
- Tap to confirm
This action will:
- Remove all trusted computers from your iPhone
- Reset permissions for apps that use location, camera, microphone, Bluetooth, etc.
🔄 The next time you connect to any computer, you will be prompted with the “Trust This Computer?” message again.
📌 What Else Is Affected by Resetting Location & Privacy?
This reset not only untrusts all computers but also reverts permissions in the following areas:
- Location Services (GPS)
- Camera and Microphone access
- App permissions (e.g., Contacts, Photos)
- Bluetooth and Wi-Fi network preferences
- Custom settings for privacy-related system features
✅ Your photos, apps, messages, and media will not be deleted. Only privacy and trust preferences will reset.
🧠 Why It’s Important to Untrust Public or Shared Computers
If you accidentally trust a computer you don’t control (such as one at a library, internet café, hotel, or workplace), that system may:
- Install unauthorized software or profiles
- Create unauthorized backups of your iPhone
- Access personal files if reconnected
- Interact with your iPhone using third-party tools
While the initial connection requires your iPhone to be unlocked, a trusted computer can later connect without additional prompts, unless trust settings are reset.
🛡️ Extra Tips to Stay Safe
Avoid Trusting Unknown Devices
Always think twice before tapping “Trust” on a shared or unfamiliar computer. If you’re unsure, tap “Don’t Trust”—you can always trust it later.
Use Charging-Only Ports
When charging in public spaces (e.g., airports or malls), use a USB power-only adapter or a USB data blocker (also called a “USB condom”) to avoid accidental trust requests or data theft.
Enable USB Restricted Mode
Go to Settings > Face ID & Passcode (or Touch ID & Passcode) and scroll to the bottom. Ensure “USB Accessories” is off. This prevents USB data access when your iPhone is locked.
Regularly Reset Trusted Devices
If you frequently connect to multiple systems, reset your trust settings periodically for added security.
🧼 What to Do After Resetting Location & Privacy
After untrusting all computers:
- Reconnect your iPhone to your personal or work computer
- When prompted, tap “Trust” only if you recognize and own the device
- Enter your passcode to confirm
You’ll also need to reauthorize app permissions like:
- Location access for Maps or Weather
- Camera use for Instagram, WhatsApp, etc.
- Microphone use for Zoom or voice messages
🆘 What If I Can’t Remember Which Computer Was Trusted?
There’s no direct list of trusted computers stored on the iPhone. If you’re unsure whether you’ve trusted an unsafe device, your best course of action is to reset all trust settings as outlined above.
✅ Summary: How to Untrust All Computers from Your iPhone
If you accidentally tapped “Trust” on a public or unknown computer, don’t worry—you can quickly revoke all computer access by resetting your iPhone’s location and privacy settings. This clears all trusted computers and keeps your data safe.
Quick Recap:
| Task | Action |
| Untrust all computers | Settings > General > Transfer or Reset > Reset > Reset Location & Privacy |
| Impact of reset | Removes all trusted computers and resets app permissions |
| Data loss? | ❌ No – Only trust and privacy preferences are affected |
| When to reset | After trusting a public/unfamiliar computer, or as a safety precaution |
