Am I just unlucky, or is there something else going on? I had one drive that had one folder disappear in Mac OS X, and Disk Utility said that there was a problem. I plugged it into a Windows computer and ran CHKDSK and it recovered the files it could (most of them actually). I then plugged it back into my Macbook, along with my Backup external hard drive to make sure all of the files were up to date and transfer some. Now, this backup hard drive has only been plugged in 5 times in the past 2 years, and has had the best of conditions. Yet now the entire backup drive is unmountable. I will say that it did throw an error during the copying of one file that may or may not have been bad on the first drive, or maybe it died right in the middle of transferring the file... Should I trust these two hard drives anymore? The first one was making some weird noise very infrequently a few weeks before it had it's problem. The 2nd backup one is like it is right out of the box. WD says that they have a two year warranty on them, but is it more hassle than it would be worth? I did buy a new USB3 hard drive on Black Friday before any of this happened, and I will have to think about what to do with it now. Do I format it as a Mac OS Extended (Journaled) drive? Are there any benefits to that since I now only use Windows to run CHKDSK? Should I buy a second one and setup a RAID array? $100 is cheap insurance compared to having to deal with this.