Can you please help me how to fix this? Thankss.

That's not a lot of information to work with.
Did it every work? What was done to it before it stopped working?
Have you plugged it into the wall to let it charge for several hours?

Oh, sorry.
It is not usable at this time.
Before it dies, it says error 517.
So I install again the OS. Then it is successfully installed.
Then when I woke up yesterday morning, I saw that it is turned off.
I didn't do anything. I'm just chatting on the BBM.
I charged it already for several times but it is not turning on.

The phone is dead but the red blight blinks one time, then 3 times continuously.
Help me please. :(

Can you try a different battery in it?

Yep.
But it won't turning on. :(