I've been trying to Google, but all of the issues refers connection from PC to remote VNC server.

So. I have an issue with VNC communication from Android to Linux. I have installed a TightVNC Server on latest Ubuntu version which works fine if I connect to it from PC with RealVNC Viewer on port 5901.

I downloaded a VNC Viewer by RealVNC for Android and if I try to connect to my remote host it says "Too many authentication failures" even on first try.

I also tried a couple different VNC Viewers, but result is exactly same.

What would be the reason and how I am able to fix it? Some people were speaking about that the client can be unsecure, but I'm not sure what difference there would be with PC and Android version of VNC.

  • From PC to remote: Works

  • From Android to remote: Doesn't work

About half-year ago on my different server I had no similar issues. It was working fine, no matter what device I used to connect VNC if I knew IP, port and password.

  • It is always better to SSH tunnel your VNC connection. VNC will lock (i.e. "too many authentication failures") after a couple of failed attempts, and, since there are a lot of people scanning ports out there, it will always happen sooner or after. Running VNC on localhost and then doing ssh -L is better (and can be safer if you use pubkey authentication for the SSH connection).
    – grochmal
    Commented Nov 6, 2016 at 4:18
  • @grochmal thank you for information. I will Google for more about SSH tunnel since I don't know how do I use it with VNC. I just wanted to comment that it doesn't make that on my PC. I can still connect there with PC and I didn't made any failed logins and login credentials has been verified to be correct. Also my server has been rent a couple days ago so I don't think about someone else trying to connect there.
    – Weird E.
    Commented Nov 6, 2016 at 5:21

1 Answer 1


When I get this error message I usually log into the server and restart the vncserver and it works again

$ vncserver -kill :1
$ vncserver

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