n. If your free disk space still isn’t where you expect it, then it really is being used by something. First, use the Windows Disk Cleanup Wizard to remove unnecessary files.

The trick is finding the files and folders that are using the space. Windows isn’t especially good at this, but there are many free tools that are good at it. My favorite is the free and tiny Scanner disk space usage analysis tool. Download and run the .exe file–no install necessary–and then examine the radial chart to find the folders using the most space. Hover your cursor over the bigger sections of the diagram to find the folders using up lots of space. If you don’t expect that folder to use that space, right-click the section and then click Open. Scanner opens an Explorer window to show you the contents. As you can see from this screenshot, my Shared Virtual Machines folder is using 17 GB–a surprise to me, since I don’t use that folder to store virtual machines anymore.

I managed to clear up about 40GB of unneeded files, postponing the purchase of more hard disks by another couple of months…