I've had this camera about 3 years. It has worked excellently up to a month ago. The lens assembly won't fully retract when I zoom or power off. Likewise, it won't fully extend and gives me a 'lens error' message. Everything else works as long as I don't try to zoom. Repair services want more than $100 to repair it, which is more than you can get a used one on eBay for! Has anyone had this problem and tried to fix it themselves? Is there a Nikon manual that shows you how to take the 7900 apart? The User manual is just that, how to use the camera. Thanks, Michael