3 ways to solve it:
1.) Take out and put battery back in.
2.) Plug into a wall or car charger but not a PC USB charger. This does not work with PC USB connection for some reason.
3.) Hold red on/off button to force a reset.
4.) The big battery icon should appear on screen.
5.) Let charge until mostly or fully charged.
7.) Turn on phone. It should boot.
2 - Hard Reset
To perform the hard reset, hold down the center select button in the
middle of the D-pad/joypad (the raised silver one.) Then, continuing
to hold it for at least five seconds, press the power button to allow
the device to power up. Continue to hold the select button until you
get a screen which asks if you want to perform the master reset. Let
go of the select button, and press the appropriate soft action key t
o respond yes.
REMEMBER! A hard reset erases ALL of your data!!! This is why the Backup is so important
You could get Sprite Backup
In addition, install it to your Storage Card and save your backups
there as well. That way you can restore on the road without
3 - Update your phone's firmware