So my external harddrive is a 320gb WD essential. It is making this horrible screeching noise when time machine does a back up or when the drive spins up. I don't know what is wrong. I only bought it 5 months ago. I e-mailed WD and was supposed to get a response back within 48 hrs. But it has been 72 hrs and still no response. Does it have a warranty? I can't find out anywhere if it does. Is it dieing? It still seems to be working perfectly. Thanks!