How To Install Windows from ISO File (No USB Drive Required)

You can reinstall Windows directly from an ISO file without needing a USB drive or DVD. This method runs the installer from within Windows itself, making the process simple and efficient.

Download the ISO

• Go to Microsoft’s official site and download the Windows ISO (Windows 10 or 11).

Mount the ISO

• Navigate to the downloaded ISO file.
• Right‑click and select Mount.
• Windows will treat it as a virtual DVD drive, showing its contents in File Explorer.

Run Setup

• Open the mounted ISO drive.
• Double‑click setup.exe to launch the Windows Setup Wizard.

Choose Installation Options

• Accept the license terms.
• Choose what to keep:
  • Keep personal files and apps (upgrade).
  • Keep personal files only (apps removed).
  • Nothing (clean install).
• Back up your files first if you choose “Nothing.”

Install Windows

• Click Install.
• Windows will copy files, restart several times, and complete installation.
• Follow prompts for region, keyboard, account, and network setup.

Finish

• After setup, you’ll land on a fresh Windows desktop.
• You may want to delete the windows.old folder using Disk Cleanup.
• No USB stick or DVD was required — everything was done directly from the ISO.

Note on Editions

When launched from your desktop, Windows checks your current registry and digital license. If you have Home, the installer defaults to Home. If you have Pro, it defaults to Pro. You can override this behavior by editing the Registry.

Editing the Registry

• Press Windows Key + R, type regedit, and press Enter.
• Navigate to:

  HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion

• Change EditionID:
  • Core for Home
  • Professional for Pro
  • Education for Education
  • Enterprise for Enterprise
• Change ProductName to match the desired edition (e.g., Windows 11 Home).
• Repeat the same changes under:

  HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\Windows NT\CurrentVersion

• Important: EditionID is case-sensitive. Do not restart after making these changes. Run setup.exe once edits are complete.

Things to Keep in Mind

• Changing editions this way does not grant a free upgrade. A valid product key is required for activation.
• Cross‑grades (e.g., Pro to Home) may force a custom install, meaning you cannot keep existing programs.

This method provides a direct way to reinstall or upgrade Windows using only the ISO file. With careful preparation, you can achieve a clean installation without external media or third‑party tools.