There may be several reasons why a laptop optical drive will not read a CD or DVD:
- Dust / dirt. The optical pickup and drive mechanism of a laptop drive is exposed when the drive is open, which means that it's relatively easy for dust and dirt to get in and degrade the drive's performance.
- Damaged drive. For the same reason, it's relatively easy to damage a laptop drive. Inadvertently touching or knocking the pickup lens may degrade performance. Also the platter (the little disc that holds the CD and spins it) may get knocked out of alignment.
- Damaged disc. A scratched CD or DVD may be difficult or impossible to read correctly. Generally speaking, a factory made disc will be more resistant to abuse than a recordable disc. The latter may also degrade quite quickly when exposed to sunlight.
Often, the problem is a combination of the above. A marginal disk may be readable in a good drive, a marginal drive may read a perfect disk, but a marginal drive will probably spit out a marginal disk.
The remedy for dust or dirt is a careful dusting off with a clean soft brush - make-up brushes work well, but only if they've never been used to apply make-up :)
The pickup lens may be cleaned very carefully with a cotton swab moistened with a drop of pure alcohol or lens cleaner.
If the drive has been damaged to the point it will no longer read a reasonably good disc, the only option is replacement - they cannot usually be repaired.
There's one more thing that may cause trouble: the computer's software. Most or all computers will read audio CDs out of the box. But especially windows systems have a tendency to get screwed up over time, and sometimes an audio CD will not play just because windows has forgotten what to do with it. Usually you can get around this by starting your system's audio player (windows media player, winamp, VLC or whatever) and tell it to play the CD.