This week Microsoft started blocking rival browsers as well as search providers from using the Cortana search box in Windows 10. Cortana is the prime search area for the operating system.

Microsoft on a post to its company blog said that to ensure it can deliver integrated search engine experiences designed for the operating systems Windows 10, Edge is the only browser that will launch when a search is completed through the Cortana box.

The search box, which is on the lower left of the desktop version of Windows 10, relies on the Microsoft search engine Bing.

Microsoft defended its move by saying some software programs will circumvent the Windows 10 design and redirect users to search providers not designed to be working with Cortana.

When something like that takes place, said Microsoft, users could be compromised and their experience could be less predictable and reliable.

While no names were mentioned, Windows 10 was modified by Mozilla’s Firefox so that when the browser was made, the default on the operating system, the selected search provider for Firefox, generated the results from queries made from Cortana, with the search pages appearing not in Edge, but in Firefox.

Other browsers, such as Chrome by Google, did not go quite that far, but extensions that are third-party and available in the Web Store by Chrome did.

The current changes will not affect any basic functionality of browsers that are non-Microsoft said the software maker. Firefox, Chrome, Opera as well as others continue to function like before and will default to their search providers when searches are made from within each browser.

However, the search box of Cortana can now only carry out Bing and Edge searches.

Microsoft has very good reason to make Cortana its exclusive territory. The company has bet on Windows 10 generating revenue outside its traditional fee from licenses that original equipment manufacturers or OEMs pay.

Not only does the software maker want to push its users toward the Edge as much as it can, but it is expecting new revenue from an increased use of search engine Bing.

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