Try the steps below first.
Put the camera switch in the Off position. 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 accidentally turned on while the lens is restricted.
Next, apply gentle pressure 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 on.
If the lens doesn't extend at all or it extends, and then retracts again, do the following. Turn the camera off. Take the camera in one hand and with the other gently take one part of the lens and gently move it round in a circular movement. Do so with both sections of the lens. You will hear a "click" as it pops back in place. Power the camera on.
Next, try to pull and twist on the largest ring of the lens while turning the camera on. Listen for a "click". If at first the focus seems to be off, turn the camera on and off and take lots of pictures, close ups and distance. Focus should slowly start improving.
A lens position error will halt the camera start up process. Lens errors are a common problem. With newer cameras I am usually hesitant to suggest these options since they include some more extreme procedures that may cause further damage if not done correctly, but they may save you an expensive repair bill or having to replace it. The links below give step by step DIY instructions on troubleshooting and attempting to fix this problem. You can disregard references to sand blockages as the cause. An older Canon camera is used to demonstrate these procedures but, the lens structure of these compact cameras is the same so the examples do apply to this unit. These procedures are effective about 60% of the time. Click on or copy the link location and paste them into your browser.
You can ignore the compressed air and cleaning procedures.
Note: Considering the age and present value of this camera, paying the cost of having it disassembled and the component replaced , approximately $75 - $100 really depends on how attached to the camera you are. The standard "rule of thumb" is if the repair cost is greater than 50% of the value of the camera, it is not worth it. A used or refurbished Nikon coolpix L620 can be purchased for about $45-$60. New ones for about $85 at the link below.
If the "do it yourself" approach doesn't work out for you and you need conventional repair please see below for repair options.
Please keep in mind that my diagnosis & solutions provided are directly dependent on the accuracy of your description of the problem. As with any "do it yourself" fixes, success is a "team effort", since I can't see or touch the camera, and relies on the customer's manual dexterity and ability to follow the instructions well.
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