The WinSxS Folder in Windows Server
The Windows component store (C:\Windows\winsxs) is used during so-called servicing operations when installing software. These operations include Windows updates, installing service packs and hotfixes.
The Windows component store contains all the files needed to install Windows components. Component updates end up sitting in this folder too. So Windows eats up as much disk space as it can find. This junk pile grows with every installed update or Windows component. The Windows component store uses NTFS hard links between itself and other Windows directories, to increase the reliability of the Windows platform (yeah, that’s really what Microsoft says).
This folder’s size won’t display quite correctly because of these hard links. For example, if a file named advapi32.dll takes up 700 KB on disk and exists both in the component store and in the \Windows\system32 folder, Windows Explorer will show it taking up 1400 KB of disk space.
After all that, it’s obvious even to a drunk hedgehog that you can’t delete this folder - the system will break. You can use the Disk Cleanup utility to remove unnecessary files. Depending on the phase of the moon and the length of a beaver’s tail during a wild doe’s mating season, you’ll free up a couple extra gigabytes of space on your server or computer.