Google cannot manually change your listed address at the exact time
you move to your new site. There are steps you can take to make sure
that your transition goes smoothly, however. Google listings are based
in part on our ability to find your site by following links from other
web pages. To preserve your ranking, you will want to inform any sites
that currently link to your pages of your change of address. As long
as the links change as you move your site over to a new location, your
PageRank should not be adversely affected.
If Google continues to list an 'old' version of your site (i.e. Google
continues to list www.my123site.org despite the fact that your site
now lives at www.my456site.org ) you need to update the links that are
pointing to the sites. Since the Google search robots jump from page
to page via hyperlinks, someone must still be linking to the defunct
page. Once others correct their links, Google can too.
One way to determine who is linking to the dead site is to try a link
search. You can find instructions on how to do this on our features
page. Please note that this process does not work for all of the sites
in the Google index.
Google finds sites through a process known as "crawling" the web. This
involves robot software that follows hyperlinks from site to site.
Google currently looks at more than 2 billion URL's during the crawl.
The process may take several weeks to complete.
I hope this has answered your question; if you require further
information, please ask for a clarification before rating this answer.
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