Hi there,

Well it's just because of lens errors, they are very common in these digital cameras. Usually it's sand or grit interfering with the lens extension mechanism. 

Follow the below steps to do a try to correct it -
1. Remove the batteries from the camera, wait a few minutes. Put a fresh (or new) set of batteries back in and turn the camera on. If that didn't work, try pressing and holding the Function or OK button while turning the camera on. (We know that you camera battery's are in good condition but the newest battery help better).
2. Blow compressed air in the gaps around the lens barrels with the idea of blowing out any sand or grit that may be in there jamming the lens. Other variations include blowing with a hair dryer in “no heat” setting, or sucking the gaps with a vacuum (careful with this one).
3. Place the camera flat on its back on a table, pointed at the ceiling. Press and hold the shutter button down, and at the same time press the power-on button. The idea is that the camera will try to autofocus while the lens is extending, hopefully seating the lens barrel guide pins back into their slots. If further you have the same problem it means there is a gear-motor alignment of the lens which moves in and out with the help of motor. This part is replaceable at an authorized Samsung Service Center. Aprox repair cost is $120.

You can follow the below link for tech support -

http://www.samsung.com/uk/info/contactus.html

Good Luck!!

Thanks for using FixYa!!