NEC 3450 weird problem

Hello, I have a NEC 3450A DVD RW that came with my DELL Dimension 8400. I have this weird problem where the drive can perform a dvd data burn on DVD-R media fine but then ONLY the NEC 3450A DVD RW drive can read/recognize the burn afterward. All other drives will not read the DVD. Does anyone else have this problem? I did a few ISO burns with no problem. I did a few data burns on DVD+R with no problem. Only data burns on DVD-R are giving me this weird result. Is it the media, is it the drive or is it the burning program? Any help will be much appreciated.

Media - Fuji 16x
Burning Program - Nero 7

Thanks.