== Depends upon the Drive ==
make model... '''It is a hardware issue''' the region change count/setting is kept in the firmware for the drive, even reinstalling your OS will not change it. The restriction is demanded by DVD copyright owners, just like standalone/external DVD players ''(which in many cases can't be changed)''.
''There arefirmware hacks for some drives'' out there,
'''APPLE may/can reset it in a situation like yours''' as I understand it "certified techs" can reset the firmware about three times... your purchase/move of the computer may qualify... don't know if it would be free or not.
'''USE VLC''' or a third party DVD player app.
'''If this answer was helpful please remember to mark it accepted.'''
Good Luck,
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