Is it possible to upgrade to High Sierra if your OS and Home Folders are on different drives? Is there any way to upgrade without shifting everything to my internal drive? I've got a 2014 iMac with a 512GB SSD drive and external 4TB thunderbolt drive. The SSD holds the OS and the external drive holds my Home folder. This iMac is running OS X Yosemite since I purchased it, but now I would like to upgrade tp High Sierra. I've heard horror stories about setups like mine locking up because the internal drive has the new file management system while the external is Mac Journaled. Any recommendations?