Dave
There's a very good utility by the name of WinDirStat. It will analyze your disk, and show you exactly how much space is taken by each file, in a graphical format. Selecting each region on the graphic shows you which file(s) and the sizes being consumed.

It can be downloaded from this link

You might more scientifically study just what is actually on that disk.


BIAB & RB2026 Win.(Audiophile), Windows 10 Pro & Windows 11, Cakewalk Bandlab, Izotope Prod.Bundle, Roland RD-1000, Synthogy Ivory, Session Keys Grand S & Electric R, Kontakt, Focusrite 18i20, KetronSD2, NS40M, Pioneer Active Monitors.