Sony Update Engine Failure (error 100)

[RonanN1]

Hello.

I got a message to update my phone software, when I conected my phone to my pc, and after I started the process i got the Sony Update Engine Failure (error 100) message. Now I CAN'T USE MY PHONE. Every time I start it i get the message:

the software update failed make sure that your phone is connected to the computer and try again

What now?

And please don't tell me to delete/restore my phone because i'm not gonna do that. I have important data on that phone and I'm not gonna delet it just because you can't make something work ok.

Thanks.

[Johnwithsony1]

Hi!

Got "new" Sony Xperia Z2 tablet (wifi) with Android 4.4.2

Tablet do not find any Android OS updates via WIFI.

So I tried Sony companion stf with Software Update  option or Software Repair option, got the same error

UELoginAuthenticationFailed
UE_1100
1.5.12.0 / Windows 7 SP1 64 bit / Win32 / US / SGP511 / 17.1.2.A.0.314

My other Sony Xperia Z3 tablet is working fine wiht same PC & Sony companion sft...