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Clean Install Windows

Guide on how to backup your data and clean install Windows.


Prerequisites

Another clean system if your current system is infected with File infector malware.

Why?
Because file infector malware can copy itself to the bootable USB that you are going to make to perform a clean installation.
You need to use another clean system to make a bootable USB and plug it into the current infected system only when it's not running live Windows.
How to check if you have file infector malware?
Open PowerShell as admin and enter
sc.exe start "sppsvc" > $null 2>&1; Write-Host "Error code: $LASTEXITCODE"
If the output is 577 or 225, then most likely chances are that the system is infected with File infector malware.


Back up your data

The clean installation process will format the C drive where Windows is installed; if you have any data in the C drive, you need to back it up.

  • You can copy your data from C drive and paste it into other partitions.
  • Your data is usually located in the below place on the C drive,
    • Go to this folder C:\Users and then select the user account that you are using.
    • Your data is saved in Desktop, Documents, Downloads, Music, Pictures, and Videos folders.
    • Save these folders in another partition to backup.

tip

It's highly recommended to backup your critical data on some online drive as well, for example,
GoogleDrive - 15GB Free
Mega - 20GB Free
OneDrive - 5GB Free


Create a bootable USB with Rufus

  • Plug your USB drive into the system. (Its data will be deleted.)
  • Launch Rufus which you downloaded earlier.
  • In the "Device" dropdown, select your USB flash drive.
  • Boot Selection:
    • Click "SELECT" and choose your Windows ISO file. Rufus will auto-configure optimal settings.
  • Click "START."
  • Wait for Rufus to create the bootable USB. It may take several minutes. You'll see "READY" when done.

Reinstall Windows

  • Disconnect all external or non-boot internal drives to reduce installation risks.
  • Restart your PC and boot from the USB flash drive, typically accessed by pressing F11 or F12 during startup. If it's not working for you then google for example "Asus Zephyrus G14 boot menu key" and find the results for your model number.
  • Follow on-screen instructions.
    • Choose "Custom: Install Windows only (advanced)" for a clean install.
    • Delete all partitions on the boot drive, or if you want to save data partitions then delete only the C drive and other small system partitions, and select the unallocated space created.
    • Click "Next" to start the installation. Windows will auto-create the necessary partitions.
tip