sony ericsson k770i?

I just bought this phone from ebay and it seems fine apart from the camera.

When i go to take a picture it says 'open lens cover' even if it is open. At this point I shut the lens cover and open it again and it either doesn't notice and still tells me to open it, or it registers it and allows me to see through the camera on the screen. After getting this far, I go to take a picture, but it cuts out. The camera screen once its registered that the lens cover is open only stays on screen for a few seconds and then just cancels back to the main screen without giving me time to take a photo.

Is there anything I can do about this?