Hi!

Sorry my first post is a plea for help...

I upgraded my S2 to the latest config using Kies - nothing exotic just standard.
The upgrade seemed to go well and the phone rebooted ok.
I then updated snapchat and put the phone down.
10 Minutes later the phone was very warm and refused to turn on.

I was then told that the data on the phone was precious (!!) and now need to recover that data.

Yes, I know, I should have done a backup

There are no signs of life.
I have tried:

Taking the battery out for hours and retrying
Taking the battery out for hours, holding the on button down for a few seconds, replacing the battery and retrying
​

By 'retrying' I mean trying to turn it on and/or trying to get it into up or download modes (whilst pressing the home key and the volume up/down key whilst restarting)
I have done all these with the original battery and with a charged battery from another S2. I have checked the original batter works in that other S2 too (it was fine)

I made a 'jig' in the hope that it might help - but nothing happened.

Whatever I do, the screen remains resolutely off.

If I try to charge the phone, it gets hot near the camera but does not particularly help.

Is there anything I have missed or could try?

What are my available next steps to data (and ideally phone) recovery?