There are lots of ways you can recover Windows 10 disk space. Most of these involve built-in Windows utilities so they don't require any additional time, effort or expense to acquire, install and use.
Some techniques produce better results than others, and some third-party tools work more efficiently than what Microsoft bundles with the OS. On a typical Windows 10 installation -- discounting post-upgrade cleanup -- you can expect to recover 5 to 10 GB of space, but it's possible you could get even more. Here's how:
File cleanup frees disk space
The first category of space recovery comes from file cleanup. Disk Cleanup is the name of the basic utility that is baked into Windows. You can run it by typing Disk Cleanup into the Windows 10 search box, or by opening File Explorer, right-clicking on the drive you wish to clean, selecting properties from the resulting popup menu, then clicking the Disk Cleanup button. Either action produces a window that looks like this:
When engaged in serious cleanup activity, it's smart to click the Clean up system files button. That way, the cleanup utility will include system files among the checkbox items made available for removal.
Two free third-party file cleanup tools include Piriform's CCleaner and Josh Cell Softwares' UnCleaner. CCleaner is a general-purpose cleaning tool that does a good job, but be sure to get the Slim version of the tool. It omits advertising code from its installation. UnCleaner primarily targets temporary Windows OS, cache and application files, but it does a good job of finding and removing them. It's a good idea to use either Disk Cleanup or CCleaner and UnCleaner to recover Windows 10 disk space periodically.
Remove obsolete device drivers
Over time, Windows accumulates a lot of outdated device drivers. On some never-before cleaned systems, you can free up 4 to 5 GB of disk space by flushing obsolete drivers from the %Windir%\System32\DriverStore folder. You can use a free open source utility called DriverStore Explorer -- aka RAPR.exe -- to identify and remove unneeded drivers. Download and install the utility, then right click RAPR.exe and select the Run as administrator option to use this program. You must next click the Enumerate button, after which you'll see something like this:
By default, RAPR won't let you delete drivers in use. For a first-time cleanup, click the Driver Class heading at the top of the window, then attempt to delete all members of individual driver classes one at a time. The program deletes unused drivers and leaves drivers in use alone. That makes it quick to work through even large numbers of drivers.
Cleanup the Component Store
The Windows Component Store is a huge directory of files and file links that permeates the Windows file structure. It resides in a folder named WinSXS (%Windir%\WinSXS). There's almost always room for cleanup in the Component Store, but it's nothing you can or should attempt directly. Turn instead to the Windows Deployment Image Servicing and Management utility, aka DISM.exe. It must run with administrative privileges to do you any good, so press the Windows key plus X, then select Command Prompt (Admin) from the resulting pop-up menu. Here is that window with the command string to illustrate the syntax you'll want to use:
DISM provides administrator access to Windows images, which is why it must run in Admin mode. The /online switch tells the tool to operate on the version of Windows that's running at the moment, and /Cleanup-image tells the program it will be performing image cleanup activities.
The /StartComponentCleanup switch tells the program to compress those WinSXS components it elects to keep, and to delete outdated or no-longer-used components. And /Resetbase compacts the Component Store, but it also disables your ability to roll back recent items introduced via Windows Update. Include this switch only if you're willing to live with the consequences, or you have a backup image you can roll in to replace the results.
Don't forget there's still opportunity for some manual labor in the cleanup process. Look through your Documents and Downloads folders at least once a month, as well as Pictures and Music if you use them, to see what you can delete or relocate.
Microsoft recommends that the system/boot drive always have at least 25% free space to give it room to work. Keeping down the dross and flushing old, unwanted stuff not only clears out the clutter, it also helps contribute to a happier and healthier system. Get in the cleanup habit and you'll help yourself stay productive, and you'll know when it's time to start thinking about upsizing your system drive.
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