Guys, let me also contribute to this very interesting discussion.
I must admit I find this kind of "extreme" WinSxS removal an interesting exercise but also one that is not really productive in the end. Mrpotter2510 refers above to "winsxs removal without breaking Windows Update" as a "mystery". Well, it is hardly any mystery at all. I would recommend reading some information about what the winsxs is and what it does. Granted, Microsoft did a poor job of how it had been handled up to Windows 8.1. But with the latest Windows release there is very little sense in my opinion to continue "reducing" and "cleaning up" this folder. Windows (at long last...) can do a pretty good job of that on its own.
With Windows 8.1, Microsoft also added an important DISM command switch, which is "Dism /Online /Cleanup-Image /AnalyzeComponentStore". You can read more about it here http://technet.microsoft.com/en-us/library/dn251566.aspx. It shows (among other things) how much of the WinSXS size is shared with other Windows folders. Running it now on my Win 8.1 x86 installation shows that my WinSxS folder is 1.90 GB but 1.71 GB of it is shared with Windows - meaning these are all hard links to various Windows folders.
Now, without going into technicalities, the NTFS file system implemented since NT4 supports a feature known as hard links. It provides the ability to keep a single copy of file which can appear in various (multiple) folders. The important thing is that hard links do not take any additional space. A file may appear to be located in 10 different folders but it still occupies as much space as it does as a single file.
To put it simply, WinSxS folder actually IS Windows (since the days of Windows Vista). What we see in all other Windows (and Program Files) folders are only hard links to the files residing in all those thousands of WinSxS subfolders. Unfortunately, Windows Explorer can't properly handle hard links and treats them as separate files, occupying additional space. The above DISM command can partly remedy that. There are also external programs that can help to avoid this confusion. I recommend the excellent Hardlink Shell Extension from Hermann Schinagl (http://schinagl.priv.at). After installation, it adds a few two things to the system, including easy creation and deletion of hard links. Importantly, it adds an additional tab to file (or directory) properties in Windows Explorer, which lists (any) existing hard links. Right-clicking on a file and choosing "Properties" and then the new "Link Properties" tab will show the type of link, its reference count and enumerate the hard linked files in their folders. The other handy feature is a small red arrow in the left lower corner of any file that is hard linked anywhere on the disk. This way, you can have a quick look at any Windows and Program Files folders and see what's going on.
OK, so what does cleaning up the WinSxS folder do? Deleting most of the files from this folder DOES NOT yield any significant space gain. What happens is that the files do not reside in the WinSxS folder anymore but are instead "moved" to their appropriate Windows directories (that is actually not entirely accurate but I will just leave it like that for the sake of simplicity). That also explains why deleting a file from a Windows folder (in most cases) does not result in any space gain, unless we also remove the hard linked file from the WinSxS.
Another important feature added to Windows 8.1 is one more new DISM command switch. This one is actually used by Winterstorm as a means of cleaning the WinSxS on the first system boot up. What is important about the "/ResetBase" switch added to ""Dism /Online /Cleanup-Image /StartComponentCleanup" is that it "removes all superseded versions of every component in the component store" (once again, have a read on
[You must be registered and logged in to see this link.] What it means is that after adding Microsoft updates and running this command all "older" updated file copies are removed from the WinSxS folder. Up until Windows 8.1, the WinSxS kept growing and growing as Windows kept all file versions, and these were not hard linked. If you looked into the WinSxS on Windows 8 or 7, you could for example see 10 or more shell32.dll files in separate folders, each occupying nearly 20 MB (again, I'm simplifying things as there was an update to improve that by means of file compression).
To sum it up, the whole Microsoft's concept of deploying and servicing Windows installation is based on the WinSxS folder. Its integrity is the only way to keep Windows Update intact. "Extreme" cleaning does not yield significant space gain. Sure, there are files in WinSxS that are not hard linked anywhere, but they are kept for various reasons (plug and play comes to mind as an obvious example) and I know far better ways of spending time than hunting for and deleting those files.
I'm all for reducing the bloat of Windows but, as I mentioned elsewhere, my priority will always be a FULLY working Windows installation, an important part of which is Windows Update. What I find really great about Winterstorm's Windows Reducer is that it keeps Windows Update fully working. There are other programs out there to slim down Windows 8.1 that use a more "elegant" package-oriented approach throughout, similar to what is implemented on Winreducer's "Integrated Default Features" tab. The only problem is that this approach makes it very hard to have fully working Windows Update - most updates will install just fine but some will error out and refuse to install (speaking from hands-on experience
).