Sometimes games doesn't work on xbox 360 like cod 6, the problem is that i cant play the single player (compaign) part. It shows the error of ( clean **** and restart the console .....) even i changed that DVD still that error goes but i can play the multiplayer part easily ?

Try cleaning the disk, if that doesn't work, try another disk, if that doesn't work, then turn the xbox off, take the hard drive out, put it back in, then try playing the game again.

You should totally get one of those lens cleaning disks and use it on your xbox. if that doesn't work contact me with specifics. K

There is really big chance for an Xbox 360 to completely ruin a game disc if it was moved while the disc is spinning inside, even the slightest bump or vibration could higly cause for a disc to be scratched. This also happens with other optical drives which has spinning motion, say DVD/CD players and other game consoles.

If your Xbox 360 does not have display you need to stop the heat getting to the chips. You can actually do this yourself as many have in this forum using the recommended Xbox 360 Repair guide.

Basically the guide will show you how to stop the heat build up with videos and household items, of course if you are in doubt send it in.

It has a preview video on the website.

Or of course you can send it in to have it fixed.

some of the reg xbox games dont work on the 360

Try to clean out your xbox 360. Or, try to clean the disc with a soft rag and windex. Or, your disc is scratched

there have been scripting errors on COD:WaW where it has trouble with the graphics card. when you turn it on, does it say 'error code E74'? if so, you will need a new graphics card.

Try and clean the DVD drive first.If that don' work you need to get a new dvd drive.

Halo will allow you to play with several guests on the non-competition section of their system.

But most ( maybe all ) CoD will only let you use a single account for one player when playing online.

The only option would be to have your friend purchase a 360 and join a party/game with you.

Is this COD??
If so back up your gamesaves from COD to a meme stick.
Then put COD in and see what happens.
If it works then the game save was corrupt.
And yes you will have to start again.