Sorry ,just noticed your post...If you have XP you need to disable the Xp burning soft.Go to my computer>right click on the writer Icon>properties> recording>disable it.
Uninstall your version of nero and get a version from cdrsoft or ..
h**p://kickme.to/cdr-dl
Then see if the copies can be read,if not get the cdwriter upgrade from Windows update..(XP only)