Originally Posted by phil_

device manager>>dvd/cd-rom drives>>double click the dvdrw
drive>>region>>select the right country and click "ok"
keep in mind you can only change the region 5 times and cannot change it anymore after that (regarless to windows reinstallation , its a hardware thing) you might wanna consider purchasing "dvd region free" or use a 3rd party region free firmware to bypass that

dvd region free - http://www.dvdidle.com/dvd-region-free.htm
3rd party firmware - http://www.rpc1.org
if i were you i would go on the software solution,dvd region free