I've just bought a Advent notebook. I have used an LG external DVD rewriter to plug in to the notebook so that I can watch a DVD - worked perfectly and watched DVD's without any problems. Due to making a mess of something else,two days ago I used system recovery to take the notebook back to its factory settings. Now when I plug my re-writer in, its says 'Windows Media Player cannot play this DVD because a compatible DVD decoder is not installed on your computer' - Yet I played the same DVD last week? Any clue as to whats happened? Much appreciated. Windows Media player 9 is current installed on the notebook.