Why does my xbox read only some discs?

are you sure i don't need to do anything else? Not trying to downgrade your intelligence, i'm just confused because some discs work, and others don't. If the laser was bad, wouldn't it be that no discs are readable, even CD's and burned movies? Thank you for helping me by the way. This is my very first console. I bought it very recently-used.

You are not "downgrade" my" intelligence" at all. It is actually pretty smart on your part.

The reason for that is the wave length of the laser. You need a different wavelength for burned CD and music CD's versus commercial DVD's etc. If the laser is weak it will no longer read the disks. Regular CD-ROM drives use a wavelength of 780 nanometers (nm) to read discs, the same wavelength required by CD-R and CD-RW discs. DVD uses a wavelength of 650 nm. Regular mass-produced CD-ROMs are very reflective and can be read at a variety of wavelengths, so the 650 nm is not a problem for them. However, CD-R and CD-RW discs are not as powerfully reflective at other wavelengths, and a 650 nm laser has trouble reading them.

That is why my suggestion is always to check the laser for debris first. Specially something like your console that is at last 10 years old (just had to replace my own drive in a 2006 model, same symptoms as yours). Hope this makes sense. Let me add the adjustment on the pots for the laser to my answer. See if that will temporary resurrect your drive.

Thank you so much! I will try that first. That definitely makes perfect sense. I never thought that a different laser type would be needed for different discs.

We all are learning something new every day.....:)

So I cleaned the laser and it still doesn't read halo reach. However, it does easily read official movies now. I don't know how to make it read games.