Hi,Thank you for using Just Answer my name is ***** ***** I will help you with your question.Many Camera faults are caused by dust and grit getting into the lens workings and stopping it coming out or stopping sensors working out where the lens is.Sometimes tapping the camera into your hand when turning the camera on or off can help with freeing stuck lenses.If you have access to some air in a can or air compressor you could try gently blowing some air around the lens to see if that will help.There is some good information here on camera repair.http://camerarepair.blogspot.co.uk/2007/12/fixing-lens-error-on-digital-camera.htmlIf you need a camera repairer this company seems to repair most cameras.www.camerarepairworkshop.co.uk
Is the battery fully charged?
Where you near a beach? sand and grit are the most common for causing a lens to get stuck. You could try brushing around the lens with a paintbrush to see if you could remove any sand/grit that could be stopping the lens coming out.Is the camera under warranty?
I find that air is the best at freeing lenses if the air has failed to free the lens the only other option would be stripping the camera and cleaning it manually, it could be the lens motor has failed and needs replacing.A new lens is available on ebay.http://www.ebay.com/itm/Orignal-New-Lens-Zoom-Repair-Part-For-Samsung-ST66-ST64-ST68-ST76-ST78-Silver-/380559071633It would be a fiddly job to replace the lens but it you wanted to try it yourself I would offer as much help as I could.There are disassembly videos on youtube I have not watched them but, they might be worth a watch to see if you feel you would like to tackle repair yourself.
If it makes a noise it is more likely that the lens is just stuck, you could continue to try bumping the camera on your hand while you turn it on and see if it will free up.I repair electronics everyday i don't find it too difficult to strip a camera it is just very small screws and small connectors that make it fiddly.
If you have any problems or you need more advise feel free to ask. I would have a watch of the videos first so you have an idea on how it comes apart.