Why is my phone showing an unknown symbol?

[Windows Central Question]

My Phone Is Showing An Unknown Symbol

My phone was working pretty well until about a day ago. I was turning it on and the it turne off for about five minutes and started showing a symbol I havent seen before. Because of this I cant do anything wihh my phone (nokia lumia 520). It just shows this is symbol until the batteries dies.

Its a large lighting bolt and then next to it is a smaller wheel (like the settings logo)

Does anyone have any clue what this is and how to fix the problem because I'm getting desperate at this stage

 

[Scienceguy Labs]

Re: My Phone Is Showing An Unknown Symbol

I'd try a soft reset first. If that didn't work, I'd download the Nokia Software Recovery Tool and give that a go.

 

[MDK22]

Re: My Phone Is Showing An Unknown Symbol

YES, perform a HARD RESET

This can be done via a (side)key combination / sequence which will revert the device to factory. ALL data will be lost.

Search the web for 'Lumia 520 Service Manual' ... @ the very end of the manual, there is the key combo / sequence to initiate a hard / factory reset. I have the key combo for my Lumia 1520 (& the Lumia 920) but both have non-removable batteries - the key combo for yours could be different.