Nec2500A won't read a back up dvd without errors

I just installed a Nec 2500A drive into a friends PC along with an OEM version of Nero 6 .After the install I burned a copy off of a back up using disc copy and it came out fine, now that he has taken the pc home when trying to use disc copy he gets read errors. I went into "extras/Nero Drive Speed" it doesn't seem to recognize the drive as a DVD recorder but his XP Prof. O/S does in my computer. The menu in Speed Drive only gives two read speed boxes ,but it doesn't specify "cd read" or "dvd read speed" like it should . Any info would be appreciated, thanks