Ok so I have 2 hard drives installed and three partitions, HDD 1 SSD <----- Mac OS X HDD 2 NTFS Partition = Windows 10 HDD 2 exfat Partition = Shared between Windows 10 & Mac OS X I don't know why this has to be such a constant struggle but upon almost every reboot the exfat partition completely disappears from the OS X desktop and I have to run fdisk to repair it and then reboot again only for it to disappear again upon another reboot. Yes I have to reboot fairly often as I boot into Windows for various software and tools that I need to use so this is extremely time consuming and frustrating to constantly deal with the inept exfat management of OS X. It has never gotten better over time either, in fact I would say it is worse in El Capitan than it has ever been, the fct that El Capitan's GUI Disk Utility is now hobbled just compounds this issue, forcing me to always use terminal now to recover said lost partitions on a daily basis. It doesn't matter if I use chkdsk in Windows or fdisk in OS X, that exfat partition still constantly disapears. I am guessing its either OS X or Windows that is destroying the boot region of the disk where the exfat partition is? If I had to narrow it down I would guess that its OS X doing so and not Windows as Windows exfat managements seems to be pretty on point. Sorry for the ranting nature of this post I am just getting frustrated. Anyone have a solution OTHER than not using an exfat partition?