BOOTCAMP partition cannot be mounted After working in Windows for a couple of days, then booting back to OSX - I cannot mount my BOOTCAMP partition in Mac OS X any more. Disk utility shows BOOTCAMP as "greyed out". Trying to mount throws an error "The disk BOOTCAMP could not be mounted. Try running First Aid". I cannot run First Aid because it is also greyed out.

I still can boot into Windows just fine via alt/boot. Moreover even Parallels can boot the Bootcamp partition just fine! (I mean, from OSX, as a virtual machine).

PS. I'm using Yosemite, and Windows 10 Bootcamp.

PPS. If I do this:

# cd /Volumes
# mkdir /Volumes/Bootcamp
# sudo mount_ntfs /dev/disk0s4 /Volumes/Bootcamp


It works fine. But it mounts it readonly, also I want it to mount automatically on startup, like it was before...

UPDATE:
After digging through the system log I found this: "Windows is hibernated. Will not be able to remount read-write. Run chkdsk." - A-HA! This must be it.

But its not hibernated... Ok, guess I have to boot into windows again and shut-down/restart it a couple of times to clear the hibernation flag...
Basically, what worked is booting to Windows natively and shutting it down several times to clear the hibernation flag. Also, disabled hibernation via power-management and via powercfg /h off.