To set a default location
Click the Start button, and then click Control Panel.
Search for location in search box and then click Enter a default location.
Enter a postal code. If you want to provide an address, you can enter it under Enter an address (optional).
Click Apply.
Administrator
permission required If you're prompted for an administrator password or confirmation, type the password or provide confirmation.
more details and reference at: http://windows.microsoft.com/en-us/windows7/set-a-geographic-location-for-your-computer