I have a MacBook Air running Sierra. I've just plugged in an old 16GB external hard drive (FAT32) via USB. MacOS won't see it at all. I've tried running Disk Utility and even that doesn't see the drive. But plugging it in to a Windows laptop, it works fine (it was originally used with a Windows PC). So it's not the USB cable or the drive. Any ideas on how I can connect to the drive on my Mac? Thanks.