Hotpoint Mistral Plus 8596 FridgeFreezer?

Hi, just looking for some advice really. My f/f is showing the error code E8 and it is about 10 years old. It has been in the garage for about 2 years. The freezer is ice cold and the food in it is still frozen, the fridge seems cold enough and only has beer in it anyway! Do I need an engineer? Can I do anything to resolve it? Indeed is it fixable at all? Is my food ok to eat? (I only put it in there over the last week or two). I would really appreciate any information on where to go/what to do first.
Many thanks.