problem when archiving a commercial DVD

Hi everyone,

I have been trying to archive a commercial DVD. I used Roxio Creator
to make a copy on a DVD R DL. I used the Copy Disk functionality, not
the Save and Burn Image functionality. Everything went fine, I did not
get an error message. However the DVD player of my PC does not play
the DVD I created.

I am guessing that this may be caused by protections on the commercial
DVD. Could it be a problem with Windows Media player? How hard is it
to archive a commercial DVD? I am surprised that there was no alert
from Roxio Creator, does that make sense? I am going to try to play
the DVD on a different DVD player.

I greatly appreciate your help.