If you have installed a 3 terabyte hard drive or larger but Windows 7 recognizes only 2 terabytes or less, I’ll show how to fully use your hard drive capacity.
1. Right click Computer and then click manage from the drop down menu.
2. Click on disk management, located on the left pane.
3. Locate the drive, right the blue band and click Delete Volume on the the 2TB partition. Once deleted you’ll notice the entire drive becomes unallocated.
4. Now right click on the “Disk #” box and click on Convert GPT Disk. you’ll immediately notice the divider disappear making it possible to use the entire drive.
5. Now lets allocate the drive to make the drive usable, to do so right click on the black band and click New Simple Volume… and continue to click on next and finish on all the Wizard windows