I've tried searching for answers to setting up the external drive on this forum, but haven't found a suitable response so apologies if this has been answered elsewhere. I recently moved from PC to Mac (15" Retina MacBook Pro) and am a bit of a newbie with Macs. I have a 2TB WD external drive and I'd like to set it up as below: 4 partitions: 1. Time Machine backup (400GB) which I must be able to encrypt using the option in Time Machine preferences 2. (500GB) to store my mac data 3. (500GB) to store my wife's mac data 4. (600GB) to store windows and mac data. Must be able to be read by PC and Mac. So far I've erased the drive to MS-Dos format and created 4 partitions as above using Disk Utility. The (600GB) drive is set to FAT and the others to Mac OS Journaled. Partition scheme set to Master Boot Record. Everything seems to work fine but the problem is I can't seem to encrypt the time machine backup...the Encrypt Backup option is greyed out for some reason?? Any idea how to set it up as above? thanks!