Windows Inside & Out · Troubleshooting Windows · Lesson 4 of 5

Reset This PC, Step by Step

Reinstall Windows safely: the choices, what gets removed and what to save first.

The two big choices

Reset this PC is a built-in tool that reinstalls Windows. It is a big step, for when the smaller fixes have not worked. It often cures a PC that is slow, crashing or full of strange problems, because you get a clean copy of Windows.

To find it, open Settings, choose System, then Recovery, then click Reset PC.

The first choice is the most important.

• Keep my files reinstalls Windows but keeps your personal files, such as documents, photos and music. It removes the apps you installed and puts settings back to normal.
• Remove everything erases your files, apps and settings. Use it when you are selling or giving away the PC, or want a totally fresh start.

With Remove everything, Windows may offer to clean the drive. This can take hours, but it makes your old files much harder for anyone to recover. Turn it on if the PC is leaving your home.

The second choice is where the fresh copy of Windows comes from.

• Cloud download gets a fresh copy of Windows from Microsoft. It needs internet and downloads several gigabytes, but it works even if files on your PC are damaged.
• Local reinstall rebuilds Windows from files already on your PC. No big download, but if those files are damaged, it may fail.

With good internet, cloud download is often the more reliable choice. Local reinstall is handy when the internet is slow or missing.

Before the reset starts, Windows shows a summary of your choices. Read it before clicking Reset. The PC restarts several times and can take an hour or more. Keep it plugged in.

On a Mac, the similar idea is Erase All Content and Settings, or reinstalling macOS from macOS Recovery.

Before you reset: back up and find your key

Even with Keep my files, back up first. A backup is an extra copy of your files kept somewhere else. If anything goes wrong during a reset, the backup saves you.

Before you reset:

• Copy important files to an external drive or to cloud storage such as OneDrive.
• Make a list of the apps you use, so you can reinstall them later.
• Have your Wi-Fi password and account passwords ready. You will need to sign in again.

What gets removed? With Keep my files, apps you installed yourself are removed. That includes things like Zoom, games and printer software. Apps that come with Windows stay. Afterwards, Windows puts a list of the removed apps on your desktop, so you know what to reinstall. Get them again from the Microsoft Store or from each maker's official website.

The BitLocker recovery key. Many Windows 11 PCs use BitLocker or device encryption. Encryption scrambles everything on the drive so only your PC, with your sign-in, can read it. After a reset or a big change, the PC may ask for a recovery key, a 48-digit number that unlocks the drive.

Find the key before you start. If you sign in to Windows with a Microsoft account, the key is usually saved in that account. On another device, go to aka.ms/myrecoverykey and sign in with the same account. Write the key down or print it, and keep it somewhere safe.

This matters. Without the key, a locked drive cannot be opened, and not even Microsoft can get the files back.