DVD Drive not appearing/mounting

[RocketPenguin]

I have been using Ubuntu on my laptop for a long time now, and have been using 12.04 since it cam out. Now, my DVD drive used to work, on 12.04, but for some reason, one day it just didn't pop up when i placed a disk in. According to my laptop, i don't have a DVD drive. It used to work, but now doesn't! It stopped working a while ago, and thought it would pop back like it disappeared, but that never happened. Now, i need it, but it doesn't mount, is what i think it may be. My laptop is an Compaq 6910p HP laptop. I can hear my DVD drive rev up, then stop, so it has power, but seems as if it doesn't exist.

[dandnsmith]

Optical drives are always more difficult with laptops, as the tend to be special drives and are less accessible.
Your sort of problem could be a cable partially unplugged - not too likely as you say it revs up (but does it only do that at boot time, or will it do it if you insert a disc?)
Another possible reason is that the drive has aged, the laser has degraded so much that it cannot perform (drive needs replacing)
The most positive thing you can do is to use a lens-cleaner disc, which can remove grot and, possibly, get the whole thing working again.

Do post back when you have more info.