Example pulled at random:
D:\analysis\Windows\WinSxS\amd64_microsoft-windows
-imageres_31bf3856ad364e35_10.0.15063.0_none_edd17c6c30b4bf9f\imageres.dll
...
- Total: 4435
D:\analysis\Windows\System32\imageres.dll
...
- Total: 4435
I am willing to bet those are the same file hardlinked and only wastes the 4435 bytes once, verifiable thusly: cmd> fsutil hardlink list \Windows\System32\imageres.dll
Windows\WinSxS\amd64_microsoft-windows-imageres_31bf3856ad364e35_6.3.9600.16384_
none_cd7c033dcbdd0cab\imageres.dll
Windows\System32\imageres.dll