Wi-Fi authentication problem after a night sleep

Hi! After installing Android 5.0.2 to my Sony Xperia Tablet Z, I am facing a strange issue with Wi-Fi connectivity. When at home my device is continuosly connected to wi-fi. But after several hours, basically I notice it in the morning, there is an "Authentication Problem" with wi-fi, and I need to reconnect it. In wi-fi settings I have set "Keep wi-fi on during sleep" to "Always", it doesn't help though. Any ideas how to fix it? Prevously, on Android 4 wi-fi worked flawlessly without any problems. Thanks.

Authentication error trying to tether when unlocked

I have a network unlocked ATT LG G4and I am on mobile share plan that allows tethering. I have no problem tethering in the US with my ATT SIM card.

However, when I use another SIM card (for data in europe), I get a message "authentication was unsuccessful" when trying to activate the hotspot.

If I put the same SIM into my galaxy S4, have no problem activating the hotspot and tethering.

Any idea what's going on? Clearly the foreign SIM is fine. And the phone is capable of tethering (on ATT).

I posted this under ATT G4 as well, but I'm not sure if it's particular to ATT.

Authentication error with WiFi tethering abroad

I am unlocked and I am on mobile share plan that allows tethering. I have no problem tethering in the US with my ATT SIM card.

However, when I use another SIM card (for data in europe), I get an authentication error when trying to activate the hotspot.

If I put the same SIM into my galaxy S4, have no problem activating the hotspot and tethering.

Any idea what's going on?

[Q] Stuck after Factory Reset - Email Authentication (Galaxy Core Prime)

Hello guys!

I work at a smartphone repair shop fixing phones both hardware and software issues. A customer came in yesterday, they just bought a Galaxy Core Prime from T-Mobile (SM-G360T). The same day she was partying, setup a password to unlock the screen and couldn't remember it the next day.

I told her I could remove the password however she would lose pics & docs since we had to do a factory reset.

A few hours later she came back in and showed me this weird loop the phone is going thru. It asks to setup a Wi-Fi and enter her gmail account. Upon entering the gmail account it goes back to same screen to accept terms, enter Wi-Fi, etc.

I concluded this is the copy of Apple's iCloud lock, obviously, albeit it seems filled with bugs. If that is the case then what is the website I can go to remove the lock - same thing as going into iCloud.com and removing "Find my iPhone" - that would remove the lock for android? Does google even allow removing of this feature online?

I have checked email/pass the information is legit, all the email notifications are there.
My other alternative is download a different ROM (since I can't find the T-Mobile one, seems it just came out - SM-G360T) and try restoring via ODIN, however, I'm not sure it will work since I've done a factory reset, thus removing USB Debugging.

Help me out if possible guys, thanks in advance!

2nd user authentication error!

Hi All,

I have the wi-fi only Z4 Tablet and my wife uses it with a second user account however she is constantly asked to Authenticate and then taken to a Google login screen.

Once the email details are correctly inputted it accepts it in Google but the authentication app fails so becomes unusable which is a joke.

Is this an Android think or Sony feature?

Some screenshots attached and thanks in advance.

Sent from my XT1254 using XDA Free mobile app

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