Unable to erase a cd-rw on my Sony dru 810 - A

media memorex 4X Cd-Rw
i am unable to erase the data on the cd

im useing nero 6.6.1.4
every time i erase it erases then when i put it back into the drive to write again all files r intact :confused:

im on win xp sp2

plz help me

Try DVDInfoPro.