Usually the "Protected" message indicates that a positive and negative speaker wire are touching. I would recommend unhooking and reconnecting the speaker wires - both on the speakers, and in the back of the unit - to see if that help.
If not, it may be that the unit requires service. If that's the case, you can call 800-SAMSUNG for further troubleshooting and if necessary, to set up a repair.
i have inserted my usb in the player but after 30 minutes of watching a movie my dvd player shuts off, and when i try to watch again it closes again after a while, And i observed that every time it shuts off there is the word PROTECTED that flashes in my dvd front panel....can you help how to fix it, its a samsung HT-TZ212 model