when I try to verify the disk it just gives me an error, I tried erasing, and partitioning the drive, am i doing something wrong, I knmow it is mac compatable, also, in disk utility, it shows two drives, the first says external usb etc, then under that to the right, it says disk 1s3, what do I do to which?? Also, the disk does not show up on my desktop but does on disk utility