No, partitions don't change on their own. They must have been so from the start (unless you or somebody else changed them).
Why not start using such a big empty area of your disk?
Kees
I am running an old xp laptop and was getting a "low disk space" message. When I looked at my disk volumes I see that an unnamed partition has a capacity of 5.01 GB with 16%free. My C:drive capacity is 13.97GB with 6%free. And my D:drive capacity is 55.55GB with 99%free. I didn't partition the drive myself, and it has been years since it was done. I have no idea what the partitions volumes were originally. Is it possible for them to change on their own? I don't know any reason for the D:drive to occupy such a large portion of the disk.

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