system
6
I have the same problem.
I am a premium user (pay regularly every month) and I also can’t set anti theft to work anymore on my wife’s phone.
I can set it up on my phone any time (s4,stock android 4.3). My account gets recognized and everything works fine. But when I try it on my wife’s galaxy i9000B (android stock 2.3.3) , I get the AUTHENTICATION_FAILED when trying to link it to her account (same message if I try to link it to my account). I’ve been trying it for a month.
I doesn’t seem be to a Google problem, since I can do it on my phone. Also, it is very odd that the message pops up almost instantly after clicking… It is like there wasn’t even any attempt to communicate.
I must say that we had anti theft working on her previous phone (galaxy s3 - got lost). This new one uses the same number as the old one, but I don’t think that’s the problem. I have upgraded my phone several times, keeping my SIM number, and I have always reinstalled avast without any issue.