Nero express not recognizing both

I have a sony DRU710A, and up until last week had that same toshiba dvd rom drive listed in my sig. the DVD rom freaked out one night and died. A friend had an extra DRU710A and gave it to me, so I now have two burners in my comp. Whenever I try to use nero express to back up a cd it thinks I have one drive and prompts me to take out the orig and insert the blank disc, when I never had to do this previously, DVD shrink and clone and decrypter do not have this problem, anybody got any ideas on how to fix express so it knows it should burn from one drive to another? thanks

okay a friend of mine admitted to changing a setting, I hadnt realized anyone had messed with my system, I was informed by the person in question, and it was corrected, it was something I never touch…sorry for the post