there are many ways to get it work again (at least to try to)
the best way is this:
Turn off the camera. Place it on the back with the lens facing up and take a look at the spacing between the lens and the lens housing. If you notice that the gap is not even all the way around the lens, the problem should be easy to fix. This type of a problem usually occurs if the camera was dropped while the lens was extended. Simply - VERY GENTLY - press down the lens on the side where the gap is the biggest. You should hear a “click” as it pops back into place. Try powering the camera back on.
i've found it on the net, here is the original text - if that won't help - go to the source page and read about the other options
Lens errors are fairly common. Usually it's sand or grit interfering with the lens extension mechanism. Or the camera's been dropped with the lens extended. Or the camera has been powered on, but the lens had been blocked preventing its extension. Or the battery ran down with the lens extended ...
Unfortunately, many cameras that fall prey to this can only be corrected by professional repair. But, here are some things that you can do that may correct it. They only seem to work for less than 40% of the lens errors, but if the camera is out of warranty, they're worth a try.