Camera is stuck on 'connecting computer' screen, help!

Recently tried to use my camera after a couple of years and the moment I press the power button, it turns on but gets stuck on a black screen with the words 'connecting computer' on it. the lens won't open, I can't use the camera or the buttons and even when I connect it to my computer nothing happens.

Does anyone know how to fix it or what the cause of it is?

thank you!