1, Enter the command prompt
Start -> cmd
2. Start diskpart
3. Find the drive that has the wrong size
4. Select the volume (in this example we use volume 2)
select volume 2
5. Extend the volume
*Note the "extend filesystem" and not just extend, this is because our space is allocated and just not correctly reported to the NTFS system so it is necessary or you will ge the failure below"
Diskpart successfully extended the volume
Virtual Disk Service error:
The size of the extent is less than the minimum
*I don't know why the above error happens,normally it is if the partition cannot extend that far because the next partition or volume is next but this is not the case on this system.