Federated search enables users to search remote data sources from within Windows Explorer. Remote data sources make themselves searchable with a simple web front end that exposes their search capabilities. In fact, some data sources may already support the minimum requirements for search federation. You can easily create a Search Connector for your favorite website as follows.

Copy-paste the following template in Notepad.
<?xml version=”1.0? encoding=”UTF-8″?><OpenSearchDescription xmlns=http://a9.com/-/spec/opensearch/1.1/ xmlns:ms-ose=”http://schemas.microsoft.com/opensearchext/2009/”>
<ShortName>TheWindowsClub</ShortName>
<Description>Search TheWindowsClub with Live Search</Description>
<Url type=”application/rss+xml” template=”http://search.msn.com/results.aspx?q={searchTerms}+site:thewindowsclub.com&num=10&format=rss”/>
<Url type=”text/html” template=”http://search.live.com/results.aspx?q={searchTerms}+site:thewindowsclub.com&format=rss”/>
</OpenSearchDescription>
Now simply replace the terms highlighted in red with parameters of your choice. That is Your site name, site description and site url.
Save the file as an .osdx extension file.
Source : MSDN.
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