WinSxs Stands for "Side by Side" most dlls or system exes are located
here for your operating system, older ones for compatibility or the
programs you use as well as previous versions from system updates, you
should not delete or modify the contents of the SxS folder cause windows
preforms its own cleanup and management of this folder itself any
modifications can cause severe problems with your windows installation.

Google has some extensive docs available about this folder and its
operation.


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dmex