New Windows 7 feature in KB 2852386...
New Windows 7 feature in KB 2852386 reclaims wasted space on your C: drive
Microsoft's new patch lets you clean up Windows bloat from earlier patches and quickly reclaim 1GB to 3GB of space
Think of the WinSxS folder as a Windows elephants' graveyard. When Microsoft patches Windows, it sticks the obsolete versions of earlier files and their settings in the WinSxS folder -- typically C:\Windows\WinSxS. That way, if you want to roll back a patch, Windows Update can pull out a previous version of your machine's programs and settings, then restore them properly...
Full story available at InfoWorld,
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