A little idea to suggest, which I'm not sure if it'll work. Sandra will confirm the yes or no:
Right click "My Computer" on the desktop.
take "Manage".
choose on the left side the computer components or perepheric.
On the right side take the DVD drive and right-click one of them if you have two.
Take "Property"
Take the tab "DVD Region"
Maybe there you can modify or do something. Or at least I hope for you.