sorry to hear about this. You might be facing a mainboard problem with the camera, which would be unfortunate as the camera is out of warranty.
You should try all other solutions that are safe before trying more desperate measures that could brick your camera.
The thread below might help, but if you read to the end, the person had to replace the camera (under warranty in his case).
If it’s out of warranty and you considering throwing out the camera, you can try the file system techniques.
Before you take this step, did you try deleting all the pictures from the SC with the USB cable? Maybe there is data corruption on the internal (not user serviceable) SDCard.
Before you throw out the camera, you can try and take it apart and access the SDCard (not recommended unless you’re desperate).