My website affected by Panda update on September 2012. I loose all my ranking. So i started building backlinks for generic text, naked url backlinks and related keywords. Slowly i started gaining my ranking and few keywords comes to page 2. and few in page 1. Then on October 2013, it again affected by humming bird updates. and from that time to till now all ranking gone. So now what to do? 1) should i forget this website and build a new website 2) should i disvow all 47000 backlinks in google disvow tool and start new backlink building 3) or should i build normal backlinks as ?