Last Updated on December 5, 2015 by Dave Farquhar
I found this trick yesterday for freeing up disk space on tight Windows 7 installs by using an automated tool to purge the C:\Windows\Installer directory. Windows 7 users with monster HDDs won’t have to worry about this, but if you’re running Windows 7 on a small SSD, you will.
But what if everything in C:\Windows\Installer is in use, like it was on my machine? Compress it!
You can right-click in Explorer and select Compress, but there’s a faster way.
Open an administrator command prompt, then issue the following command:
compact /c /s c:\windows\installer
Then it will buzz through the contents of the directory, telling you how much space it saved on each file, and in the end, you get a grand total. I was able to save 200 megabytes. Not a lot, but not chump change, either.
While you’re at it, there are some other directories you can give the same treatment:
c:\windows\inf
c:\windows\help
c:\windows\logs
The return on investment there is more likely to be along the lines of tens of megabytes, but again, it costs no money and a minimal amount of your time. You can switch to another task and check back in a few minutes to see what you saved.
The more space you can free up on a small SSD, the better the wear leveling will work and the longer the drive will last. Although I haven’t actually tried this myself, the theoretical life expectancy of an SSD running at 90% capacity is around 3 years.
David Farquhar is a computer security professional, entrepreneur, and author. He has written professionally about computers since 1991, so he was writing about retro computers when they were still new. He has been working in IT professionally since 1994 and has specialized in vulnerability management since 2013. He holds Security+ and CISSP certifications. Today he blogs five times a week, mostly about retro computers and retro gaming covering the time period from 1975 to 2000.