Windows Vista: Service Pack 2 Cleanup

I am using a LG C1 Express Dual tablet PC for a few weeks. It came with a fresh Vista image, which on connecting to the Internet underwent long hours of Windows updates, pulling itself through Vista SP1 (Service Pack 1) and later Vista SP2.

After these updates, I saw that the free space on C: had reduced quite a bit and ran Treesize Free to check out the situation. I found the C:\Windows\WinSxS directory occupying a lot of space!

It turns out that the WinSxS directory keeps components from all old updates so that uninstall (and rollback) of updates can be supported. Since, SP2 is a pretty significant update, I am not interested in keeping the files from the updates older than SP2. If you are sure of this, you can recover a lot of space by running the Windows Component Clean Tool (compcln.exe).

compcln.exe resides in a super-long-name directory inside C:\Windows\WinSxS, but it is hardlinked to the C:\Windows\Sytem32 directory. So, to execute it, open cmd and type:

$ C:\Windows\System32\compcln

Press Y when it asks for confirmation of cleanup. Running compcln.exe recovered ~1GB of disk space on this tablet PC.