Make sure your battery is securely in place and also make sure that your charger actually works, as it may have failed depending on how much you use it, if you charger does work, plug it into your laptop AFTER you have checked that the battery is securely in place, leave it on charge for about 30 minutes, and then check to see if it powers on. If it still doesn't work, then you may have a hardware issue, and as it is probably out of guarantee now as it is 4 years old, you may want to think about getting an upgrade. Also, open it up and check to see if everything looks OK, as it may have water damage, or your HDD may have failed. Hope this helps, and good luck getting it working again!