How do I extend my C drive?
From: Extend a Basic Volume
You can add more space to existing primary partitions and logical drives by extending them into adjacent unallocated space on the same disk. To extend a basic volume, it must be raw or formatted with the NTFS file system. You can extend a logical drive within contiguous free space in the extended partition that contains it.
I can extend my D drive, but not C. I suspect the problem is that the unallocated space is not "adjacent", but I have no clue how to change that.
How can I solve this?