adb: device unauthorized. This adb server's $ADB_VENDOR_KEYS is not set
The phone hasn’t accepted your computer’s RSA key for USB debugging yet.
Exact message you may see
device unauthorizedunauthorized (adb devices)This adb server's $ADB_VENDOR_KEYS is not setTry 'adb kill-server' if that seems wrong
Seen on:
Android
Meaning
The first connection shows an “Allow USB debugging?” dialog on the phone. If it was dismissed, the key revoked, or the adb keys regenerated, the device stays unauthorized.
Common causes
- Prompt on the phone not accepted (screen locked)
- USB debugging authorizations revoked
- adb keys changed (~/.android/adbkey)
- Charge-only cable/USB mode
⚡ Quick fix
- Unlock the phone and accept the prompt (tick Always allow)
- Revoke authorizations in Developer options and reconnect
- Restart adb server
Detailed fix by platform
ADB
- kotlin
adb kill-server && adb start-server adb devices
How to diagnose
- Phone — Prompt visible?
- Keys — ~/.android/adbkey present?
- Cable — Data-capable?
🔧 Still not fixed?
Many errors look alike. If the steps above didn’t solve it, one of these is probably what you’re facing:
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Other ways to find it
Where this error sits
Origin: On your device. Errors that are often confused with or caused by this one (click to open):
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Last updated 13 Oct 2026