[ahyun]

Battery of my lumia 800 was gone so I charged but it didn't happened anything!

There was no sound, no sign(even the red battery sign neither). On the screen there is nothing until now. 

I've tried to connect with charger, soft reset(volume key + power), hard reset(volume key + power + camera) as well 

but nothing worked... I don't know why is it happened and what should I do....

[jimmyireland]

Try pressing the power button for around 8 seconds,if this fails id return device to NOKIA care point or point of purchase

[caitlin1759]

This happens to mine every time the battery needs charging. It happens even if I plug it in just add the "goodbye " message appears. It's a complete pain but try warming the phone up by holding it in your hand (or one time I put it under my cat which was sleeping on my lap!) Phone will start to feel warm which may be enough to kick start it. Has worked so far although like you at the moment my 800 is also a dead brick.

[jimmyireland]

This is the proper hard reset method

Power off, then reboot holding Power, Volume Down and Camera buttons, hold all three once phone begins to boot release power ONLY and hold the others, phone will be hard reset.
Images, Music and Video can be synced with Zune on your PC and synced back after reset. Contacts Caledar etc will come back when you set up your live account again.

[caitlin1759]

To the OP if I were you I'd try the warming it up and soft reset before you try the hard reset to avoid losing data. Mine has come back from the dead after 14 hours on a wall charger and 3 hours of the body heat of a sleeping and obliging cat.

To the poster above me I am well aware of the threads about how to deal with a frozen or bricked phone having reasearched them the first time my 800 went dead. It is perfectly possible to revive it by the various methods suggested but why it should be necessary to coddle and cajole it back to life when all that any other phone needs is a connection to a wall charger, is for me, a mystery and a major design flaw.

[jimmyireland]

if you think holding the phone in your hand to make it warm works well no comment there..

[caitlin1759]

Oh it works as is plainly demonstrated in several threads. The quote below is by aspergerguy . It may not be a good idea but on the several occasions the phone has bricked it's the only thing that worked. A hard reset wasn't possible as pressing the buttons did absolutely nothing. Heating it may well damage it.Lumia is relegated to spare phone, but since unlike my other spare phones, including an E72 ,which happily recharge from dead, the option is warm it or keep it as a brick.

"If you warm up a fully depleted battery because it excites the molecules you will get a bit more power released just for a short period, which might perhaps be sufficient to kick start device; it is however not to be recommended as could so easily damage plastics within the device."

[LEDJPS]

I don't think you need to heat the phone so hot that it would damage it. Just warm it enough to get the battery going .