Pulling it off on a standalone player is going to be probably near impossible depending on the unit. Its easy to do on a PC, you can use software that spoofs the region and will play anything, or buy a "region free" dvd rom drive on ebay or something for cheap, and it will play anything/never ask about regions. Those are your primary options.

Non-region free DVD-rom drives on a computer can be changed 5 times before the hardware will lock it out, not sure if flashing the drive will reset that, I've never tried. Another option is to have 2 dvd drives in your pc and set one to the region for the other discs, and one to the USA region, and use the appropriate drive depending on which disc you want to watch. DVD drives are SO cheap now that its a super simple way to do it.

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