My PC has a hard disk of around 460 GB
C: being almost full (60 GB), and D: occupying the rest of the disk, I succeeded to have a free space of 100 GB, reducing the size of D:
To do so, I first decreased D: by 100 GB (everything via normal Windows management tool)
But as the free space with after D: not before, I created a Z: disk there, moved all D: data to Z:, deleted the D: and renamed the Z to D:
But not when I try to increase the C:, the option to increase it is disabled
How can I fix this ?