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it depends. that Option can often help a little bit with scrapers if you are going to run a blog (scraping WILL happen if you have worthy content). otherwise, there is not a real need to that. see this thread for more info. this other link is mentioned in there for modifications to this theme's metadata and settings.

Check your .htaccess file to see if something is going wrong there. Another possibility could be that you did something wrong in the robots.txt file. It could also be a server issue but since we users can see the page just fine i'm thinking it's either the .htaccess or robots.txt file. Let me know if you fix it and if not i'll try to help some more.