Ahh, the mysteries of altering the FIRMWARE of the DVD DRIVE.
In short, NO ONE will be there to support you in this endeavour. It's very much an UNDERGROUND HACK.
Given the cheap price of DVDROM drives, you can just try it and see what happens. But don't be surprised if the drive just fails after the firmware change.
Sorry, but it's not supported, or supportable.
It's why I suggestted an alternative that works.
Bob
Firstly I'd like to thank those who have replied to my previous posts, in particular Bob - thanks for being so patient with a complete novice!!
I've been researching different DVD drives and at the moment I'm most tempted by an MSI one which is RPC2. Could somebody explain simply to me the steps I need to take in order to be able to play DVDs from regions other than my home region (which is region 2? Preferably using free software, seeing as many programs seem highly expensive!
Do I first need to convert to RPC1? Will I need to use a firmware patch, since I understand that these can potentially be dangerous?
Thanks in advance!

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