Updated on August 18, 2026 in #dev-environment

Checklist Before Formatting Windows

If you plan to reinstall Windows or maybe switch over to Linux, here's a few things to check and confirm before wiping your drive.

Over 20+ years I’ve formatted my fair share of Windows installations. There’s always that sinking feeling in your stomach after you’ve formatted that you might have forgotten to back something up. These steps can help avoid that feeling.

I always prefer doing a full wipe instead of keeping personal files in between installations. That means nothing about your original installation will remain.

Here’s what I check before formatting, these aren’t in any order:

• Everything in C:\Users\yourname:
  • I don’t use these directories but if you use Documents, Pictures, Videos and the others, certainly go through them in detail
  • The hidden AppData directory has all sorts of files (cache, temp files, configs and more), don’t skip this one and its sub-directories
• Go through C:\Program Files and C:\Program Files (x86) to help get a list of what you’ve installed in case you forgot, sometimes important files can be saved here like saved games, it really depends on the app
• For any tools you use, think about how you’ve configured them, their configs might be saved in your user’s directory but it could also be in the Windows registry or under program files, it depends on the tool
  • There could be important things you haven’t touched in a while like OBS recording settings (bitrates or ffmpeg flags that are easy to forget, etc.)
• If you have trouble finding where a tool is configured you can always take screenshots or pictures with your phone of important settings
• If you use your downloads directory as a dumping ground, go through it in detail
• If you created any custom directories in C:\, look into them
• Check your C:\Windows\System32\drivers\etc\hosts file for custom changes
• Any custom fonts in C:\Windows\Fonts
  • Speaking of fonts, there’s also smoothness / clear type Windows settings
• Various Windows settings:
  • Wallpapers, themes, taskbar configuration, display settings, etc.
  • Scheduled tasks, environment variables, firewall rules, policy adjustments, etc.
• Check your startup folder for anything you might have added (AutoHotKey, etc.)
• Browsers:
  • I personally don’t like to stay signed in or sync anything to the cloud so you may want to export your bookmarks, history, settings and passwords
    • Exporting your passwords is especially important if you’re not using a dedicated password manager
    • Exporting everything else mostly saves time, but if you’ve done custom tweaks having those settings exported helps
  • Check which extensions and themes you’ve installed and their configurations
  • Do you have multiple browsers? Repeat this process for each one
• Password manager:
  • If you’re using a fully offline one that’s saved on the partition you’re formatting, back it up for sure
  • If you’re using a cloud based one, make sure you can still access it
• If you have license keys (including Windows itself) saved somewhere, find them
• Certain sites let you download MFA / 2FA recovery codes, don’t forget them
• If you’re using Docker Desktop, are there volumes you want to back up?
• If you have WSL 2 instances, go through its directories and files, for example maybe you have source code or tool configuration that’s not saved anywhere else
  • Start in your user’s home directory, and don’t forget to check hidden directories like ~/.ssh for SSH keys, GPG keys, API tokens or ~/.config for config files
  • Beyond user config files, if you installed and configured other tools you’ll want to figure out what you installed, this will depend on which distro you used
• Don’t forget your saved games that might not be synced to the cloud
  • These can be in a bunch of different spots, including your user’s directory as well as Documents or under C:\Program Files (x86)\Steam\userdata
• Custom device driver or device settings, such as the buffer size in audio interfaces, GPU, network card, sound card, printer or anything you might have configured in device manager or device specific tools
• If you’re using old drivers for certain hardware, make sure you know where to download them from or even better if you have the installer for them, back it up in case the site no longer exists
• Know which version of Windows you have now and the version you plan to use after formatting as it can help with troubleshooting, you can find this under System -> About
  • For example “I was previously using Windows XYZ build 123 and now after going to version X / build Y this tool that used to work isn’t working”
• If you’re upgrading to a newer version of Windows, confirm your hardware, apps and tools you care about are supported
• If you’re planning to switch to Linux, you may want to find alternative tools:
  • For example I replaced IrfanView on Windows with mpv on Linux, foobar2000 on Windows with rmpc on Linux, etc.
  • The DotFriedRice project has a ready to go Linux desktop and has docs on how to install Arch Linux too

# Tips Before Formatting

If it’s been a really long time since your last format you might want to consider cloning your drive before you format it. This way you have everything saved in a separate working drive in case you want to boot from it later. This comes in handy after you have your new system set up so you can check old files. Personally I’ve never done this but if you’re not super experienced, it could be worth it.

Besides cloning your full drive, you should very much consider having some semi-automated way of backing up the files you care about. For example I use this rsync based script to backup and restore my life’s work. Despite it being a shell script, you can run it from WSL 2 and backup both WSL 2 files as well as Windows files. I used this strategy for years before switching to Linux.

If you’ve performed backups, confirm they are there and readable.

Don’t rush. It’s worth spending the 30-60 minutes going over everything instead of quickly running though only to forget something really important to you.

If you have a few drives that are the same size or model, to avoid confusion you might want to disconnect the ones you don’t want to format so it’s impossible to accidentally format the wrong drive.

Make sure the USB stick with the Windows installer you plan to use is working.

If possible, have another computer or phone available for potential troubleshooting.

The video below mostly covers the same steps as above. It doesn’t demo anything on Windows since I wrote this post after I stopped using Windows. I still wanted to make it because I know a lot of people are still using Windows and quite a few of these steps apply to Linux and macOS too.

# Demo Video

Timestamps

• 0:10 – The checklist
• 11:51 – Tips before formatting

What do you backup before formatting? Let me know below.