To change the system region and format,
you should do the followings:

*.Open Settings via the Start Menu.

*.Type “region” into the Settings’ search box at the top right corner.

*.Select the result “Region”.
Be sure to select the one that has a green globe icon.

*.In Region window, at Formats tab, you need to select “English (United State)” in the drop-down menu.

*.Then switch to Location tab and select “United State” at the option “Home location.”

*.Hit OK to apply the change.

*.To make sure the system location will be changed, you need to restart your Windows.
And that’s all.

Now you can click or tap the search box right next to the Start button to launch Cortana.

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