Not sure you should be asking this here, but since you do:
It actually depends on the model of the player. My player have 5 times you can change the region. The it locks. If you find the proper software you'll be able to reset it 5 times, giving you a total of 25 changes. Then, of course, you can do a total reset and start all over again. :9
Some software also gives you the ability to totallly disable the counter, which is the easiest way. I'd suggest you run a Google search for your player model.