here are the download address for firmware of jiake i9500w:
Here is the download address for the flash tool:
Pls note, before you flash the phone you need to install the drivers on your pc.(The driver will be installed aotomaticly when connected with PC)
1:Open flash tool
2: Choose the right file
4: Power off your phone and Connect your phone with your pc using the cable
5:The only thing you can do is waiting now. It should take 3-5mins. It will show 100% at last. then you can turn on your phone directly.