RE: "Your battery has expired permanent failure and needs to be replaced"
Even with the adapter connected the battery can wear out after about 2-4 yrs of use. Try removing the battery and use the adapter alone. If that works use it as a desktop replacement until you can buy a new laptop. Batteries need to be Dell replacement batteries and can be expensive and difficult to get depending on model and age. It is not worth spending a lot of money on an older laptop. It is better to buy a new computer.