[IrfanSharil]

My Nokia Lumia 1520 won't start. It stays showing the warning (!) icon. What should I do?

So yesterday before I go to sleep, I switched my phone off and go to sleep. The next day when I woke up, whenever I press the power button to switch on it shows the white warning icon (!) on black screen. Now I can't use my phone, help me what should I do?

[HareKrsna7495]

Try charging up the mobile for an hour, and then turn it on

[jeetu4444]

Try charging it....or else try a soft reset.....

sent from lumia 1020 or note 2

[rdubmu]

Your phone battery might be dead. Another option is to do a soft reset. First hold down the power button and wait for it to turn off if that doesn't work try this at your own risk- Hold down the power button and the volume up button - this could damage your phone so do this at your own risk.

[IrfanSharil]

Charged for one hour. Still the same. Even with soft reset, it still shows the warning (!) logo.

[elvandar]

When you see the exclamation mark:

Press, in this order: Volume UP – Volume DOWN – POWER – Volume DOWN

That should fix it.