How to reset Xperia Z Ultra

First Method :

Not many Sony Xperia devices have a physical button to hard reset the handset in case it freezes, but Sony is starting to include them. The Xperia ZL has one and so does the Xperia SP. Well it looks like Sony has also included one in the Xperia Z Ultra. A small red button is included in the microSD flap in which you should use a pencil to reset the phone by holding it down for 5 to 10 seconds. Make sure you don’t use anything too sharp to press the button otherwise you will damage the button, trust us, we talk from experience with the Xperia SP. The picture below shows exactly where you’ll find the button.

Second Method :

At the very beginning you should download the PC Companion, in example from

 here:This web Page
Then, you should install and run it.
Next you will see window with 4 options.

Choose option "Support Zone New!", and click "Start".

Wait for the program to install the appropriate add-on.
After that you will see next window with 3 options.

Go to option "Phone / Tablet Software Update", and click "Start".
Select "repair my phone / tablet".

Now follow the instructions and accept all informations.


Please be patient and wait until preparing computer for software update is complete.

Afterwards choose your phone / tablet model.

If you see this window, then connect your device into your PC.

Good job!

Third method:

Firstly, download flashtool from Sony website:Here
Make sure, that you have installed drivers for your USB data cable.
Afterwards turn your device off.

Then press and hold Volume Down, and connect to USB cable.

Follow the instructions on your screen, and accept appropriate options.
Success!

WARNING !
Hard Reset will erase all of your data
All described operations you are doing at your own risk.