I opened the lens cover the lens moved out and the camera went off. Now it won't do anything even when I put a fully charged battery

Not much you can do. Switching off the camera and then on, is like a cod boot from a computer.
You could try to remove the battery for a few seconds, and then reinsert it. Then you should investigate why the lens stays out. Is it because of a mechanical problem, or came some dirt between the barrel, while the camera got wet? Try to remove any obstruction. feel if the lens can move by gently moving the barrel a little. If it goes. Don't apply force, because you could damage the mechanical or electrical parts in the lens barrel.
I hope it works. Don't forget: the battery should be charged fully.

Stuck automatic lens covers are fairly. But usually it's very easy to fix, without even opening the camera. See this link for troubleshooting steps for this problem.

I had the same exact issue.... try putting it on the charger, even if you think it's fully charged... If the light is red, leave it on the charger until it turns green, and then remove the battery for a second and then put it back in the camera before turning it back on..... try turning it on. If it still won't close, put it back on the charger. If the charger is automatically indicating a red light, that means you have exhausted your battery and will nee a new one... they cost about 5-11 dollars on amazon...... hope that helps...

Does there is something happened when you turn on the camera? If you can heard sound made by the len or the camera try to open but turn off in a second? If so, there is something wrong with the lens, and this how to fix camera lens error will be helpful. Else, if the camera are without any reaction you can check it the joint of the camera to battery is well.

do you have the lens cover open? do you get any error code or warning message? do this: make sure you have fully charged battery. close the lens cover.make sure cam is off.open lens cover by sliding it down until click is heard.if no go.close lens cover.make sure cam is off.remove the battery from cam for at least 15secs.reinsert battery.open lens cover until you hear the click.if no go try this. can you see the operational buttons and icons on the screen? if you do try to initialize the camera. touch HOME ->settings (looks like a toolbox icon) -> Main Settings (touch OK) -> [Initialize] -> [OK]. if it doesn't work service might be required.thanks :)

I had the same problem. Even though I was keeping the camera on the dock all of the time to charge it, the solution was very simple - get a new battery for inside the camera.

I bought new ones at a greatly reduced price on eBay. Now I carry one with me wherever I go in case the battery wears out/down.

I shoot a lot of videos, so it really takes a lot out of the batteries.

take out the battery wait for a few sec and then put the battery back on, then switch the camera on.
for the lens try to gently force open or close the lens.
this works on my camera. i have the same problems. hope this helps.

check out first if the battery is fully charged.and if the battery is very old.then prefer replacing the battery instead of charging.and if the battery is new,then the cover of the lens must be getting stuck up so try tapping the device from all the sides it will automatically get opened.also off the camera completely and try to move the lens door manually up and down.sometimes the gear assembly gets stucked and this makes it free to  move.

Charging the batteries was the first move. Charge for at least 14 hours, and never shoot on low batteries. If the battery gives out while you are recording to memory, it can corrupt the storage media. The lens should work normally with a fully charged battery.