I had the same issue. Lens would move in/out say 3 times but camera did not start - Power off message. Suspected jammed gears - So tried the 'gently' bang several times on solid but carpeted floor (with camera off and lens retracted). Did the trick for me.
It's the internal focusing lens assembly not functioning properly. It's not uncommon for these to jam up. I've fixed several of them, but sometimes they can't be fixed, and the lens needs replacement. A little hint...buy a used DSC-W1 on eBay with a good lens. It's the same lens assembly as the DSC-W100, and it's a lot cheaper used than the W100.
Hello, there is a problem with the optical unit (lens). Normaly when the camera is in camera mode the lens should go out. In your case it seems that for some reason the lens is stuck. Please contact your nearest Sony dealer. If you want to repair the camera yourself please tell me. I can send some additional info as well. Regards, Arpi
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