I've been using a Western Digital external hardrive for quite a while now, but all of a sudden whenever I try to open it a window pops up saying that it isn't formatted. The computer recognizes when it's connected, but it can't open it. I tried plugging it in to a different computer and rebooting, but neither worked. I wonder if the adapter could be the problem, or maybe that's just wishful thinking. Is there anything I can do to restore my files?