Interal sata drive problems

So, in my first custom PC I have four HDD's... The first is a 128GB SSD, which is my OS drive. A internal 2TB sata drive to be used as a main storage for all my files like music and movies. Another internal 320GB sata drive for experimenting with other OS'. And finally an external esata 2tb drive which is usually never on except for backing up.

This is the second time this has happened, but I have lost the ability to make any changes to the 2tb internal sata drive. And since that is the one I use the most often, it stinks.

I have tried disabling and uninstalling, but don't know what else to do. I did some searching for this issue here, but it would be impossible to look through all threads.

I am running windows 7 enterprise. Any help would be appreciated