This is the time of year when PC makers offer irresistible deals on new hardware. If you've taken advantage of a Black Friday or Cyber Monday deal to replace your old Windows PC with a shiny new model, congratulations! So, what are you planning to do with that old, not yet obsolete device?
You might be planning to hand it down to a family member or reassign it to another employee in your small business. Maybe you're going to donate it to a local charity or put it up for sale.
Whichever option you choose, your top two priorities should be safely expunging your personal data from the old device and restoring its operating system so the new owner can be productive right away. And as with all things Windows, there are multiple ways to accomplish this goal.
In this post, I'll outline the three best alternatives you have, with some thoughts on when you should choose each one. (Spoiler: The most important question is who you're planning to give that PC to.)
But first, a few things you should do before you begin resetting that old PC.
See also: Buy the laptop best for you: Windows 10 or MacOS, plus 10 more things to consider
If you're still waiting for your new PC to complete its journey from the factory to your home or office, you can put the interregnum to good use by making sure you've saved what needs to be saved from your old PC and then getting it ready for its new owner.
First, take an inventory of your legacy software (older Windows desktop apps that are not available from the Microsoft Store), and make sure you have any activation codes or installer files you'll need to reinstall the apps on your new PC. Deactivate programs that allow that option (I'm looking at you, iTunes and Adobe), and uninstall any system-level utilities such as antivirus software or disk managers. You can find a full list of these dinosaur-programs-that-still-roam-the-earth, complete with uninstall links, by going to Control Panel > Programs & Features.
Next, make sure your important files are backed up. If you use a cloud storage service like OneDrive, Google Drive, or Dropbox, any data files you've uploaded will be easy to transfer to the new PC. As an extra precaution, I recommend creating an image backup of your old PC, saving its contents to a removable hard drive. (For instructions, see "Windows 10 how-to: Create a full image backup using this hidden tool.") That backup file contains everything on your old PC. In a pinch, you can mount the backup image on your new PC to recover a lost file.
It's worth noting that erasing your files and installing a new operating system doesn't automatically wipe out traces of the old data. It remains on the disk, potentially accessible by someone with modest technical skills and disk recovery software. If you're concerned that the next owner of your PC might try to recover your old files, you should take extra precautions.
The simplest solution, on a PC running Windows 10 Pro, is to enable BitLocker Disk Encryption and set it to encrypt the entire disk. After you wipe the PC, any data left behind will be fully encrypted and unrecoverable without your recovery key. On a PC running Windows 10 Home, delete any important data files and then manually wipe the erased disk space. Open a Command Prompt window and run this command:
Finally, make sure your old PC is fully up to date. If it's running an old Windows version, upgrade it to Windows 10 now (for free!) by following the instructions in the most popular article I've ever published at ZDNet: "Here's how you can still get a free Windows 10 upgrade."
With those chores out of the way, it's time to choose one of these three options:
This is the simplest way to remove your existing installation and replace it with a clean copy of Windows 10. You don't have to mess with bootable media, and beginning with Windows 10 version 2004 you can choose the option to download a completely fresh set of installation files instead of using your current Windows system files.
To get started, go to Settings > Update & Security > Recovery. Under the Reset This PC heading, click Get Started.
For the first step of the Reset This PC procedure, you have to choose one of the two options shown here. The Keep My Files option is useful if you're planning to keep your PC, but since you're passing it along to someone else, choose Remove Everything.
You also have the option to wipe the drive clean. That precaution adds a significant amount of time to the reset and isn't necessary if you're passing the PC along to a family member or an employee in your small business. But do take this precaution if you're selling or donating the PC to a stranger who might be tempted to rummage through the deleted-but-not-yet-overwritten disk space in search of recoverable data files.
The second step, available only on version 2004 or later, offers the choice of a Cloud Download or a Local Reinstall. The only reason to choose the cloud option is if your PC has some nagging performance or reliability issues and you'd like to give its new owner a completely fresh start. If your PC has no underlying issues, skip the big download and choose the option to reinstall using the existing files.
After making those choices, you'll need to confirm your decision to reset the PC twice more. The first confirmation, shown here, offers you one final chance to change your mind about the cloud download and data wipe options.
When you get to the final confirmation screen, click Reset to begin the process. After it's complete, you'll be at the initial setup screen for Windows 10. You can safely power the PC down at that point and let the new owner complete the setup for their account.
The built-in Windows 10 Reset process works for most situations, but there's one specific circumstance where it falls short. If you own a Windows laptop that includes custom drivers and utilities to enable specific hardware features, you might prefer to reinstall a factory image supplied by the manufacturer. This option is especially useful if the PC is still covered under the manufacturer's warranty.
If the recovery image is available on your PC, you might be able to restore that image directly. Some OEMs also offer the capability to download a clean, up-to-date image as part of the recovery process. To get started, go to Settings > Update & Security > Recovery. Under the Advanced Startup heading, click Restart Now. If you see a Factory Image Restore option like the one shown here, you're in luck.
If that option's not available, you might be able to download a current recovery image from the PC maker, which you can use to create bootable recovery media. For details and download links for Dell, HP, Lenovo, and Microsoft Surface PCs, see "How to get a free Windows (or Linux) recovery image for your OEM PC."
The ultimate recovery option for Windows experts is a clean install of Windows 10 using bootable media. This option is appropriate if a recovery image isn't available and you want to reformat the system disk completely to remove all traces of your old data.
Before you begin, go to Settings > Update & Security > Activation. Confirm that your copy of Windows 10 is properly activated. If you see any activation errors listed, resolve them before continuing.
To begin the reset process, you'll need bootable installation media. Use the Media Creation Tool to download the latest installation files from the Download Windows 10 page and create a bootable USB flash drive. (For details, see my FAQ, "Windows 10 updates: How to install, reinstall, upgrade, and activate.")
Next, find the right combination of keystrokes and/or incantations to boot directly from that drive into the Windows Setup program. Use the built-in tools to reformat and/or repartition the target drive. Don't skip the formatting step, or all your old files will remain on the drive in a Windows.old folder that will be accessible to the new owner.
Finally, install Windows 10. Because you're doing so on hardware that's previously been activated, you can skip past the part where you're asked to enter a product key; Windows will activate automatically after you sign in for the first time.
Read more: How to securely erase the data off your iPhone or iPad, Android device, Windows PC, hard drives, SSDs, and flash drives