Amazing. Do you realize how much disk space is wasted from a straight Windows 8 in-place upgrade? When you perform an in-place upgrade of Windows 8, the setup saves your old Windows files in a Windows.old directory.
The exact number really depends on your original OS, how many times the PC was upgraded, additional items added in, etc., etc., but on the low end, 5GB of space could be taken up with old Windows files. On the high end, as in my example here for this post, you could have up to 50GB of old files. And, I’ve actually seen both sizes recently. I upgraded my Acer Iconia Tab W500 to Windows 8 and had a bit over 5GB of old Windows files left over. If you’re familiar with the Acer you know that disk space is an issue. On the other hand, my beefy Dell Vostro 220 (4 monitors, btw) had over 50GB of old Windows files remaining in the file system.
No matter how much space is being stolen by the old Windows files, you definitely want to invest some time into removing them, once you’re satisfied that Windows 8 is the OS for you. Fortunately, Microsoft didn’t change too much about how Windows 8 frees up disk space over what Windows 7 offered.
Here’s how to do it…
1. Go to your Charms menu, then Settings, and then Control Panel
2. Next jump through the System and Security group in Control Panel.
3. Next, choose the Free Up Disk Space item.
4. After a bit of checking the files available for disk cleanup, you’ll be presented with a list of available items to delete or clean, but the initial list does not include the old Windows files sitting on the hard disk. To get these added to the list, click the Clean up system files button.
Windows 8 will need to check the hard disk for the additional files to include in the list, but once it’s done, the Previous Windows installation(s) option will be included.
Go ahead and select the Previous Windows installation(s) option, because you’ll definitely want to remove that. However, there’s a few other pieces of the upgrade that you’ll also want to review and potentially remove. Here’s the other list options that you’ll want to decide whether or not to remove as part of the old Windows files cleanup…
Quick update. Per a comment here from Michael Niehaus, there’s a System task that is scheduled to remove old Windows files after 28 days or there is less than 10% disk space free. So, you could wait for the task to run and complete…or use the method above if you want your space back immediately.