Device suddenly unauthorized for adb I have a Samsung Galaxy S5 with Lollipop and recently broke my screen so that it is now black. adbcontrol worked somewhat okayish - I did not see the whole screen but it was just enough to navigate to my memos and share them. But now I remembered that I hadn't synced my Browser bookmarks so I started my PC again, connected the phone, adb devices showed the device - but unauthorized. 
That already happened to me once so I ran adb kill-server &amp;&amp; adb start-server but the phone stays unauthorized. Unplugging and putting it back in or restarting the computer did not help either.

Why is it suddenly unauthorized? And why can't I fix it with what I tried - because that worked already a few times...
And most importantly: Has anybody got any idea how I could make this work again (or maybe a different screen-replacing tool that doesn't require adb) ?
You can try the following:


adb kill-server followed by adb start-server
(on device) Settings -> Developer Options -> USB Debugging -- switch off and on
[Windows] Make sure you have the proper driver (your best bet is Universal Adb Driver by Koushik Dutta -- will handle any device)
[Windows] Try turning off all fancy on-the-fly anti-malware scanners/firewalls
[Linux] Make sure you have the proper UDEV rule in /etc/udev/rules.d/51-android.rules (again, universal solution: https://github.com/snowdream/51-android)
[Linux] Try using adb as root
Restart your phone 
Replug cable, try different cable, different port, remove any extender cables


I hope somthing works for you :)