How to fix your phone when it wont turn o

[Cynthia_15]

Hello,
When i turn on my phone it will just turn on then turn off repeately.. what should i do? I know its not the battery cuz its fully charged.

 

[hang-the-9]

You can try to re-load the operating system, instructions vary by phone model, or bring it into a store to have them try.

 

[will305]

What phone/Carrier do you have? When you say that it turns on and off, do you mean that it loads up to the lockscreen and reboots? (Boot loop)? Also is is rooted?