[orangepeel]

Make sure you have the master/slave setting correct on the drive.

If the dvd is the only drive on the cable then set the jumpers to master (you will find them on the back of the drive)

If the DVD & another drive is on the same cable, set one to master, the other to slave. Usually easies to use the setting from the drive you removed.

You could also use "Cable Select" but in my experience that can cause incompatibility issues.

Note that the jumper settings tend to use different layouts depending on manufacturer so don't just copy the old jumper layout unless you are sure it's correct.