if your refering to protection error there is no fix!
jim, November 2006
check your manual and you should be able to reset the player to factory settings (like you have just bought it new) as it sounds like the dvd has a parental lock code put in by the previous owner. it will mean having to tune in the tv again, but then it should play o.k. from then on.
martin, December 2004
why dont you try to unplug all the connections and leave it off for a while, about 3 minutes then try connecting it up again. Should come on