Firstly, check the size of the folder (Windows\winsxs) by right-clicking it, choose Properties and make a note of its size and the number of files and folders. To run the program, open Windows Explorer and navigate to C:\Windows\System32, look for the file VSP1CLN.EXE (the capitals are for clarity only), right-click it, select Run As Administrator then reply Y to the prompt.

Now check its size again to see how much disk space you have reclaimed, you will be surprised as it will be quite substantial.

<this is misleading giving that WinSxS contains hard links that count the sizes of files twice, read about that here http://blogs.msdn.com/e7/archive/2008/11/19/disk-space.aspx#comments>

There is no harm in running the program where SP1 was either included on the DVD or slipstreamed into the DVD before installation. Depending upon what has been installed, you may gain some disk space.

I was grateful to see the instructions outlined here, however my machine did not appear to have the file vsp1cln.exe
Upon further examination I located the file at

C:\Windows\winsxs\amd64_microsoft-windows-v..ck-uninstallremoval_31bf3856ad364e35_6.0.6001.18000_none_dc83934b9415d3b6\vsp1cln.exe

• I right-clicked and selected Run as Administrator
• Confirmed my intentions at the dialog box
• Within 1 second the process opened a command window, closed it, and the process was done.

My Windows\winsxs folder size remained at 13GB.
I then tried to run the above instructions again, no change.
I tried opening a command prompt, navigating to the file and running the process vsp1cln.exe /verbose no change, no feedback.

I will attempt to find other means by which to run this cleanup utility.