I have a storage space consisted of 3 X 2 TB hd drives in parity mode. I used the drives writing 3,06 TB of files, that means I didn't used the whole available disc space (actually 2 X 1,81 TB available and 1 X 1,81 TB as parity). I added a new 2 TB drive to expand the array. But windows calls me to add 3 drives not 1 (as I did) and keeps saying I' m using 4,6 TB. I double checked the capacity of my files and it's indeed 3,6 not 4,6 TB.
I don't understand what happened. Are my files secure? Is there a way to check the health of storage space?

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