Matthew White, 22, said he was surfing for pornography two years ago on Limewire -- a fire sharing application that allows users to trade music, movies, games and pictures -- when he discovered that some of the files he had downloaded were images of children.Matt claims he quickly erased the files."It didn't appeal to me," he said. "I was looking for women my age, so I just wanted to download 'College Girls Gone Wild' and accidentally downloaded underage pornography."About a year later, FBI agents showed up at his family's home. The family agreed to let agents examine the computer, and at first, they couldn't find anything.Investigators later were able to recover the deleted images from deep within the hard drive."I asked them, 'Where did you get that? I don't remember that.' I asked them, 'Could I access that if I wanted to?'" Matt said. "They said no."Facing 20 years in prison for possessing child pornography, Matt is pleading guilty on the advice of his public defender in hopes of getting a three and a half year sentence. He will also serve 10 years probation and have to register as a sex offender for the rest of his life.Matt's father says other parents need to be warned about the consequences of stumbling across illicit material."One day, you're going to get a knock on the door and have your child taken away for many years," he said.The FBI could not comment on this specific case, but said if child pornography is ever downloaded accidentally, the user needs to call authorities immediately. They may confiscate your computer, but it's better than the alternative.Internet searches reveal a large number of complaints from people who say they've accidentally downloaded child pornography through Limewire.