NEC Express 5800/320Lc - Manual (Page 87)

Windows Setup and Operation 3-13
4. On the [Select Disks] dialog box, enter the
amount of space to extend and click [Next].
(In this case, 1500MB is added.)
5. Check the settings on the [Completing the
Extend Volume Wizard] dialog box and click
[Finish].
6. The size of the volume is
extended.