OS X El Capitan fails on OS X Installer process

Hello folks,

I am facing a problem when updating from OS X 10.6.8 (OS X Snow Leopard) to El Capitan. I've downloaded OS X El Capitan from App Store, then I started the update process .... when it starts, it crashes. After several minutes stuck in the screen below it shows a report about failures ... but the worst of all is I can't start the "OLD" version anymore, because every time the mac tries to boot, it tries to update. Stuck in a loop. What should I do? Install Snow Leopard again and update it to every other version till get El Capitan? Have you all heard about or seen it before? Thanks 🙂