For some reason, I can't play DVDs on my computer. Windows Media Player says "Windows Media Player cannot play this DVD because a problem occurred with digital copyright protection." Real Player says "The DVD cannot be played. Key exchange for DVD copy protection failed." What should I do?
After I posted that, I found out that I could use the program that copies DVDs as a simple DVD player as well, but I still want to know why those other programs won't work. They worked before...but I don't remember what I changed.