You cannot change the country/region for your Microsoft account once it is set. The country/region where your organization is headquartered determines which services are available, the taxes and billing currency, and the location of the data center. If you need to change your organization's country/region, you must sign up for a new account, select the desired country/region, and purchase a new subscription.
For Outlook, the default regional settings can be customized, but the base currency of an organization cannot be changed after it has been set. If the wrong base currency is selected, the environment must be reset to choose the correct currency at that time.
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