Microsoft is to embed its Live Search toolbar on HP PCs, in a bid to increase its presence in the search engine market.

The computer giant also announced that Live Search will become the default search engine on browsers on all HP computers. Both features will be available on PCs sold in the US from January 2009.

While the collaboration between the two companies will boost the use of Microsoft's search platform, it could also boost support of Silverlight, Microsoft's new browser plug-in and development runtime for adding multimedia to web applications. That's because the Live Search toolbar will be built using Silverlight, meaning that the browser plug-in, which is required to view multimedia content built with the tool, will come with the computers.

Microsoft is concurrently trying to improve the distribution of Silverlight by building some of its own web pages with the technology and requiring visitors to download the browser plug-in to view the web pages.

The toolbar will also include buttons that HP will be able to customise to direct computer users to websites such as Snapfish, HP's online photo-sharing and printing service, and HP customer service.

Microsoft called the collaboration the most significant distribution deal for Live Search that the company has done. HP is the world's largest PC manufacturer, the companies said. They did not mention whether the agreement might be extended outside of the US.

Some Microsoft competitors have cried foul at previous efforts by the software giant to tie its search platform into its browser. Two years ago when Microsoft launched IE7 in beta, it set Live Search as the default search provider in a toolbar in the browser, although users can hit a drop-down menu to change the search provider to a handful of other companies. At the time, Google complained to the European Commission and the US Department of Justice (DOJ) that the default setting removes choice for users.

Google has a similar setup in Mozilla's Firefox browser, which comes with Google as the default search bar. The DOJ found that Microsoft makes it easy enough for users and computer makers to change the default setting.

Deals like the one between Microsoft and HP are not uncommon. Yahoo previously had an agreement with HP to feature its search engine on new computers, and Google signed a similar deal with Dell.

The HP deal builds on other Microsoft efforts to grow its search market share since it withdrew its acquisition offer for Yahoo. For example, Microsoft recently launched Cashback, a service that offers Live Search users money back when they buy products through the search engine from Live Search advertisers.