Okay, I went into the Bios. I hope this is the correct info. that your telling me to check. On my drive configuration it had............

Diskette Drive A: 3.5 Inch, 144 MB
Primary Master Drive............Hard Drive
Primary Slave Drive..............Off
Secondary Master Drive.........CD-ROM Device
Secondary Slave Drive...........Unknown Device

IDE Drive UDMA..........ON

Also, Showing when I GO into My computer I also have listed a drive ( F: ) Which says Removable Disk, which I didn't have before I put the new DVD drive in. Unknown device eh? Well at least something is showing up. What kind of DVD burner do you have?
A cheapee Samsung SH-S222L 22X LS. I ordered it from NEWEGG. So far it works fine and it shows up on the ( D: ) drive.Have you checked the jumpers on each drive and cabled them as suggested ? ?

Not a perfect image here but it may help:



NOTE: All drives are different....LOOK for diagrams on the plastic case above the jumper position...Like I said before.....I'm not a whiz....don't make FUN of me but, you are talking about my hard drive to check this....right ? No...both Optical drives...

Thats why i mentioned it wasn't the perfect image...but would help.

And we don't make fun...our job is to help educate.Okay, I'll have to unhook everything again and check this out. Thank you for all your help.CD-ROMS are labeled MS, SL, CS, punched into the metal case above the jumper BLOCK. Not always easy to see, but it's there.Here's a pic of a CD drive jumpered as slave. It should help you figure this out.