In windows 8, there is a feature of "fast start-up" which is somehow equivalent to hibernate. It saves your system state in hibernate.sys file so that when next time you boot up the system it takes just few seconds to start.
This feature is enables by default and most of the users are unaware of it.
But this feature cause a problem to Linux users. When you boot the Linux OS and try to mount the drives it throws the error and doesn't allow you to access it.