Hi, I want just ask you one question, I am doing SEO on my client site it was running fine since last 3 months but suddenly one month before all keywords are disappear and down the SE position I checked webmaster tools and found robots.txt is not existing I do't know how it is deleted from my site. However, I was again upload the robots.txt file and it test it from webmaster tools now it is running fine but website still disappear from Google. Let me know it happens due to robots.txt file ?