I have already watched several DVD in my PC until yesterday I bought 3 new dvd movies and played in a STANDALONE DVD PLAYER and they work fine but when I tried play in my PC using POWERDVD player, it says "MEDIA NOT PRESENT". I try other DVD dics I bought a month ago and they worked fine in STANDALONE DVD PLAYER AND IN MY PC. Is this a new DVD COPY PROTECTION? I already used DVDDECRYTER, ANYDVD AND DVDREGION CSS FREE and still cannot recognized the DISC. Any suggestion?