"put in dvd"

I hope you mean you fitted a new DVD drive into your console. All games are in DVD format and if the replacement drive can not read and detect dual layer DVD's then they will not be able to see any of the games you put in.

You can find cheap xbox 360 replacement drives at http://www.dascheap.com/replacement-xbox-360-dvd-drive-philliips-lite-on.html

Maybe1)The Xbox 360 does not recognize a disc in the DVD drive

2)Disc is "unreadable" to the Xbox 360

3)DVD drive tray will not respond or move

Every issue has its own unique cause. A disc with scratches could be an issue. You should have no problems getting this issue fixed. See if another disc does the same thing. It most likely says "Unable to read disc" because it probably can't read the disc! If I were you, I would try cleaning off the disc you are using, then putting it back into theXbox 360 and try again. It may also be scratched repetitively, which cannot be fixed and you may need to buy a new copy of the disc.The disc is the incorrect region - DVDs come in formats called "regions." These regions match the region specified in the software of the DVD player. Some games also have these regions. If the region of the DVD and that of the player do not match, the disc will not play.

This is going to be a bit long -- but very detailed, so please read it carefully. There are several reasons that an xbox 360 system will have problem reading discs. The error messages also vary from unreadable disk, no message at all but the game skips, "please insert disc in a 360 console" to "open tray." There are a few reasons this may happen:

1.Bad disc. Check the back of your disc for scratches. If it looks good (or plays fine in another console), then the disc is probably fine. Also-- try more than 1 game to be sure.

2. Bad laser. The XBox 360 has a DVD drive very similar to a PC's DVD drive inside. The drive contains a bunch of parts including a few motors and gears and a laser.The laser is the part that actually reads the disc. The reality is...with all the hours and hours of game play, lasers do eventually wear out. The laser isn't very easy to replace, but it is replaceable. You can find any and all XBox 360 lasers at the following website:

http://store.richspsxparts.com/xb360ac.html

3.Bad DVD Drive. Sometimes other components inside of the DVD drive can become bad such as the motor that spins the disk, the motors that open the tray, etc, etc. You can get a new DVD drive to just replace everything,including the laser, in one shot but there is a catch. The XBOX 360's DVD drive is tied to the motherboard using a software lock.The easiest way to overcome this lock is to buy the exact same manufacture DVD drive that is in your system now, remove the circuit board from the old DVD drive (which contains the software key) and transfer the circuit board into the new DVD drive that you purchase. If you do this simple procedure, there is no flashing involved. The following website carries DVD drives and also provides instructions on swapping the circuit board from the old drive into the new one.

XBox 360 parts: http://store.richspsxparts.com/xb360ac.html

DVD Drive Swap Info: http://store.richspsxparts.com/imnooninxb36.html

This error is caused by not having the original DVD drive in your 360. Only a professional can change your DVD drive successfully. You will need the original DVD drive to fix this problem. Without the original drive your Xbox won't be playing disc based games again. A skilled professional with the original DVD drive should be able to fix your problem.

Are you using copied CD's of Xbox games, Original Xbox 360 would read such copied game discs as normal DVD's and would show a message as "Play DVD"

To play such games it requires the Xbox 360 DVD drive to be flashed, which is called as a Softmod, if you do so you would be banned for playing on Xbox Live and such act is prohibited since it accounts to game piracy

Why you replaced the dvd drive i do not know, The problem is if you have installed a non microsoft xbox dvd driver it will not work! If your original dvd driver is broken as to why you have replaced it, contact microsoft or your local games shop for another xbox 360 or drive. You can also by a addon driver, you can see it here
http://www.amazon.com/Xbox-360-HD-DVD-Player/dp/B000JHO4L0

original xbox??..

meaning the black one???

or the xbox 360..

if its original xbox, send it for a replacement already

if its 360,
does it say reading and just goes back to open tray??

-check the time and date settings on the console, even the time zone
-check if there is any corrupted file on the hard drive
-try to load a disc without the harddrive,if this works you need to perform system maintainance on the xbox

You need a new laser and/or motor. Games require a higher RPM to play.. DVDs do not

LOL well 9 months later, I'll answer your question. EVERY Xbox360 dvd drive is "married"to it's motherboard. The communication between the drive and motherboard is encrypted with a key (aka- DVD-key) IF you don't flash the dvd-key from the original drive to the replacement then there is no way the Xbox will ever be able to play anythngg other than music and dvds. You NEED the correct key to encrypt/decrypt the 360 games so the motherboard can understand it.

You need to flash the drive with the old drive's key; otherwise the your xbox motherboard will not allow that drive to access the gameplay engine and will not allow you to play games.