What a factory reset does and when you need one

A factory reset removes all your files, programs, and settings and returns your computer to the state it left the manufacturer. Everything you installed after you first turned it on — documents, photos, downloaded software, email accounts, browser history — gets deleted. The operating system itself is reinstalled fresh.

You might reset your computer if it runs slowly despite cleanup efforts, if malware survived your attempts to remove it, if you are selling or giving it away, or if you are troubleshooting a problem that persists across multiple restarts. A reset is also the nuclear option when your computer will not start normally and you have already tried restarting in Safe Mode.

Before you start, understand that a factory reset is permanent and fast. Once you confirm the reset, you cannot undo it. Back up any files you want to keep — photos, documents, financial records, anything irreplaceable — to an external drive or cloud storage first. This step takes longer than the reset itself and is not optional if you care about your data.

Key Takeaways

  • Back up all your files to an external drive or cloud storage before starting, because a factory reset deletes everything on your computer permanently.
  • On Windows, use Settings > System > Recovery > Reset this PC, which is built into the operating system and requires no external tools.
  • On Mac, use System Settings > General > Transfer or Reset, then erase and reinstall macOS, which also requires no external tools.
  • The reset process takes 30 minutes to two hours depending on your computer's speed and whether you choose to keep or remove Windows installation files.
  • After the reset completes, you will need to set up your computer again from scratch, including signing into your Microsoft or Apple account and reinstalling your programs.

How to reset a Windows computer

On Windows 10 or Windows 11, the reset tool is built in. Open Settings (press the Windows key and type "Settings"), then go to System in the left sidebar. Scroll down and click Recovery. Under "Reset this PC," click the blue Reset PC button.

Windows will ask whether you want to keep your files or remove everything. Choose Remove everything if you are troubleshooting a problem or preparing to sell the computer. Choose Keep my files only if you want to keep your documents and photos but remove programs and settings — this is less thorough and solves fewer problems, but it is faster.

Next, Windows asks whether you want to reinstall from the cloud or from local files. Cloud reinstall downloads a fresh copy of Windows from Microsoft's servers and takes longer but uses less disk space. Local reinstall uses files already on your computer and is faster. If your computer is running very slowly or you suspect disk corruption, choose cloud reinstall.

Windows will show you a summary of what it is about to do. Review it, then click Reset. Your computer will restart several times during the process. Do not turn it off or unplug it. The whole process usually takes 45 minutes to two hours.

How to reset a Mac computer

On a Mac running macOS 12 (Monterey) or newer, open System Settings (click the Apple menu in the top left, then System Settings). Click General in the sidebar, then scroll down and click Transfer or Reset. Click the Erase All Content and Settings button.

Your Mac will ask you to sign in with your Apple ID. This is a security step — it confirms you own the computer. Enter your Apple ID email and password, then click Continue. If you have two-factor authentication enabled on your Apple account, you will need to approve the reset on another device.

Your Mac will display a summary of what will be erased. Review it carefully. Click Continue, then Erase to confirm. Your Mac will restart and begin the reset process. This usually takes 30 to 60 minutes. Your Mac will restart multiple times — this is normal. Do not force shut it down.

If you are using an older Mac (macOS 11 Big Sur or earlier), the process is different. Restart your Mac and hold Command + R when ready after you hear the startup sound. This boots into Recovery Mode. Click Utilities in the menu bar, then Terminal. Type csrutil disable and press Enter. Restart again, then open Disk Utility and erase your drive. If this sounds unfamiliar, contact Apple Support or a local repair shop — the older process is more error-prone.

What happens after the reset completes

When your computer finishes resetting, it will boot into a setup screen, just as if it were brand new. You will need to choose your language, connect to Wi-Fi, and sign into your Microsoft account (Windows) or Apple ID (Mac). This is also when you set your time zone and create a local user account if you want one.

After setup finishes, you will have a clean desktop with only the programs that came with your operating system. You will need to reinstall any software you use — web browsers, productivity tools, games, anything else. If you kept a list of what you had installed, now is the time to use it. read each program from its official website or app store rather than from third-party sites.

Restore your files from the backup you made before the reset. If you backed up to an external drive, plug it in and copy your folders back to your Documents, Pictures, or Desktop. If you backed up to cloud storage like OneDrive, Google Drive, or iCloud, sign into that service and read your files. This step can take a while if you have a lot of data.

When to call a professional instead

If your computer will not start at all — no logo appears, no sounds, nothing — a factory reset will not help. This usually means a hardware problem like a failed hard drive. Take it to a repair shop.

If your computer starts but gets stuck on a loading screen or crashes before you can reach Settings, you may not be able to run the built-in reset tool. Try restarting in Safe Mode first (on Windows, restart and press F8 or Shift + F8 repeatedly; on Mac, restart and hold Shift). If Safe Mode works, try the reset from there. If Safe Mode does not work either, a technician can reset it using external tools.

If you forgot your password and cannot sign in, you can still reset your computer, but the process is more involved. On Windows, you can reset without signing in by clicking "I forgot my password" on the login screen. On Mac, you will need to use your Apple ID to reset your password first, or contact Apple Support. If neither works, a repair shop can help.

Protecting your computer after the reset

A fresh computer is a good time to set up security habits. Install antivirus software — Windows Defender (built into Windows) and macOS's built-in protections are adequate for most users, but you can add a third-party tool if you prefer. Keep your operating system updated by turning on automatic updates in Settings. Use a strong, unique password for your main account.

Before you reinstall programs, read them only from official sources: the Microsoft Store or Apple App Store, or the publisher's own website. Avoid downloading software from third-party sites or peer-to-peer networks, where malware often hides. If you are not sure whether a website is official, search for the program name plus "read" and look for the publisher's domain in the results.

Frequently Asked Questions

Will a factory reset remove viruses and malware?

A factory reset removes most malware because it deletes everything and reinstalls the operating system fresh. However, some advanced malware can hide in your BIOS or firmware (the code that runs before Windows or macOS loads). If your computer gets infected again when ready after a reset, or if you suspect a sophisticated attack, contact a professional.

Can I cancel a factory reset once it starts?

On Windows, you can cancel during the initial setup screens before the actual erasure begins. Once the reset process starts (you will see a progress bar), canceling may leave your computer in an unusable state. On Mac, the same applies — cancel before the erase begins, not during. If you accidentally start the process, let it finish rather than force-shutting down.

Do I need the Windows or Mac installation disc?

No. Both Windows and Mac can reset using files already on your computer or by downloading fresh files from the internet. You do not need a disc or USB drive unless your computer will not start at all, in which case you would need to create a bootable recovery drive on another computer — a task for a repair professional.

How long does a factory reset take?

The reset itself usually takes 30 minutes to two hours, depending on your computer's speed and storage size. After that, setup takes 10 to 20 minutes. Restoring your files from backup can take much longer if you have hundreds of gigabytes of data. Plan for the whole process to take several hours from start to finish.

What if I reset my computer and it still runs slowly?

A slow computer after a reset usually means you have reinstalled the same programs that were slowing it down before, or your hard drive is failing. If it was slow when ready after reset, before you reinstalled anything, the problem is likely hardware — a failing drive, insufficient RAM, or an overheating processor. Contact a repair shop to diagnose it.