WinSXS folder size is a known issue – an reducing its size on Vista or Server 2008 is documented, but not for Windows 7.

This is what JDiskReports showed for drive C, Windows as well as the WinSXS folder:

After some Googling around I found this thread: which recommends the command:

dism /online /cleanup-image /spsuperseded

After few minutes, I’m down to:

That’s 4117986 bytes saved (3.92Gb) on the SSD C drive!