Help!! xbox 360 won't read discs?

I was in the middle of playing a game and my xbox 360 told me that it couldn't read the disc. I tried a few games, and a screen comes up that says "to play this disc, put it into an xbox 360 console". None of the discs were scratched, so I know that isn't the problem. My system is no longer under warranty, so I have tried opening the system up. I have cleaned the lens and everything else extensively, but I am still having the same issue. Also, I know that the disc drive isn't completely fried, because I am still able to play dvds just fine on the system. Does anyone have a fix for this, preferably without me needing to bring my system to a repair shop?