Anilrgowda

Changing domain names is not something to be taken lightly. When you do, your search engine rankings may dip for a period of between 4 weeks and 9 months, in my experience. However, for those who must change domains, here is how to minimize the consequences. 1. Properly Redirect the Old Domain

Redirect visitors from the old domain to the new domain using a 301 redirect; in layman's terms, a "permanent redirect". When the search engine robots visit the old website, they will interpret the redirect to mean that all link popularity and current rankings should be directed to the new website. To put a 301 redirect in place I recommend contacting your hosting company to have them make the change. To do it yourself visit my 301 redirect tutorial (www.stepforth.com/faq/301-redirect.html).
2. Manage Any Broken Links

If the new domain is home to the exact same website, then broken links should be a non-issue since a 301 redirect will take care of forwarding users from the old domain's URLs to the new domain's URLs.
For example, when using the 301 redirect this old URL http://www.yourolddomain.com/bio/ceo.php will automatically get forwarded to http://www.yournewdomain.com/bio/ceo.php. As a result, broken links should not occur.
If, however, the position of your website documents have changed during the move, you will need to follow these instructions for properly redirecting all traffic from the old site pages to their closest relatives on the new site:

1. Create a complete sitemap of your old website. There are several good sitemap creation tools (news.stepforth.com/tools/).
2. Create a complete sitemap of your new website.
3. Have your webmaster or programmer create a 301 redirect from each of the old pages to the new pages. Install these redirects, test them and then move to step 4.
4. Submit your old sitemap to the search engines. To submit a sitemap at Google you would use Google Webmaster Central; for Yahoo you would use Yahoo Site Explorer.
5. Now monitor Google (since it is the major player) over the next few weeks, and as soon as you see your old URLs are being replaced with the new ones, move to step 6.
6. Submit your new sitemap to the search engines -- you are done!

What was the point of all these steps? Technically you could have just submitted the new sitemap, but by submitting the old one first you will speed up the switch from the old URLs in each search engine's index to the new ones, thus minimizing the impact of the switchover.
Important: make sure to pay particular attention to the 404 error report within your website statistics program. The 404 report will provide important information on pages that may be receiving traffic but are not being properly redirected.
3. Maintain or Improve Your Page Topic and Optimization

In order to minimize the impact on your rankings, it is important to maintain or improve the keyword-related content on ranking pages. In other words, don't totally rewrite pages that were ranking for "kayak tours" without carefully optimizing them to the same degree or better than before. If you wish to play it really safe, I would just leave the content the same on the pages that drive critical traffic so that the only 'change' the search engines notice is the URL, thus minimizing any ranking penalties.






Source:How to Switch Domains while Minimizing Lost Rankings