Have you checked the jumper setting on the drive?
Is the unit installed on the same cable as the dvd drive?
Is the cable a standard 40 pin cable?
Where is the drive installed on the cable, the end or the middle connector?
Check in bios to see how the dvd drive is set. If dvd drive is recognized as secondary master, then it should plug into the end of the cable.
Then set the cdrw drive set to secondary master, and plug in middle connector of cable. If they are not installed as to accept these connections, you may have to reverse the drives or reverse the settings.
One drive set to master and connected to end of cable, the other drive set slave and connected to the middle connector of the cable.
Best of Luck.
argggh, i have installed a new cd-rw and i cant get it to work, there is power ggoing into it, i have tried windows xp help and it cant do anything for me, its not listed as one of my drives, only the hard drive, floppy and dvd drive listed, there is no updated hardware for it on the website. I run xp and am totally flumaxed now. Any ideas, please keep the answers basic as i am a flop at these sort of subjects, thanx 4 your help

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