Please Help whenever i fetch & render my webpage it shows indexed and then i go to google search results and check It shows 404 error what should i do please help.
Please check the following points or we can say reasons for the sight not being indexed:-
Robots.txt - if your robots.txt file has this line in it;
User-agent: * Disallow: / it's basically telling every crawler on the web to take a hike and not index ANY of your site's content.
.htaccess - This is an invisible file which also resides in your WWW or public_html folder. You can toggle visibility in most modern text editors and FTP clients.
Meta tags - Make sure that the page(s) that's not getting indexed doesn't have these meta tags in the source code: <META NAME="ROBOTS" CONTENT="NOINDEX, NOFOLLOW">
Sitemaps - Your sitemap isn't updating for some reason, and you keep feeding the old/broken one in Webmaster Tools.
URL parameters - Within the Webmaster Tools there's a section where you can set URL parameters which tells Google what dynamic links you do not want to get indexed.
You don't have enough Pagerank - Matt Cutts revealed in an interview with Eric Enge that the number of pages Google crawls is roughly proportional to your Pagerank.
Connectivity or DNS issues - Perhaps your host is doing maintenance on their network, or you've just moved your site to a new home, in which case the DNS delegation can stuff up the crawlers access.