I recently upgraded to Nero Express 3 and found the video codec: Nero DVD Decoder is very buggy and causes frequent runtime and protection errors on a Windows XP Pro SP1 machine. I have another media player called The Core Media Player or TCMP and that program which runs flawlessly on my machine starts to error too. When something always run 100% of the time and suddenly starts to error you know there's got to be something wrong. The error occurs when you double click a MPEG-2 or .vob file.
I troubleshot the problem to this video codec because in TCMP you can disable or quarantine certain video and audio codecs from running. After disabling Nero DVD Decoder and Nero Video Decoder from loading whenever I load MPEG-2 or .VOB file the runtime and protection errors go away. Once I enable them to run again the errors come back.
If anyone is still using WMP9 (haven't upgraded to 10 yet) when you load a MPEG-2 file check properties under video codec if Nero DVD Decoder is being used instead of some other video codec then you might encounter problems. The errors occur occasionally sometimes it loads and sometimes it errors. You can experiment by loading and closing the same MPEG-2 file over and over again until it errors.
I'm not sure if everyone is experiencing the same type of problem as I am so I'm here to find out