In many articles, you can see the guide about how to  install the official Windows installation as follows:

Download the Windows ISO file, burn ISO to the USB drive (DVD) and install it through the USB drive; or download the Windows ISO file, mount the ISO file directly, and run Setup.exe to install it directly.

Besides OS installation,  making a Windows bootable USB also requires ISO files. Then, how to get the Windows ISO file? How to ensure the image is pure? This article shows you how to get an official image file.

Get official Windows ISO files

It’s not available to directly download Windows 10 ISO file from Microsoft’s official website. But it offers Media Creation Tool, which allows you to upgrade the operating system or download Windows ISO files.

Way 1. Media Creation Tool download

Step 1. Enter the official address:

https://www.microsoft.com/en-gb/software-download/windows10

Step 2. Click the "Download tool now" button to download Media Creation Tool.

Step 3. Double click the downloaded exe file to open the tool, check "Create Installation media (USB flash drive, DVD, or ISO file) for another PC" and click" Next".

 Step 4. Select the image language, version, and architecture you want to download and click "Next".

Step 5. Choose" ISO file" and click "Next" to select the path for saving the ISO file.

Way 2. The address for directly downloading the ISO file

Take the Edge Chromium browser as an example: You can modify the browser's UA to make Microsoft Server think that the system you are using is not a Windows system (you can't run the Media Creation Tool software) and Microsoft will feedback a new page where you can download ISO file directly. 

Step 1. Input the official address in the browser：

https://www.microsoft.com/en-gb/software-download/windows10

Step 2. Press F12 Key to enter developer mode (You may need to press FN+F12 on some laptops); select the device icon as shown on the right, select any model of mobile device on the left side of this page (here we choose iPad Pro); and then press F5 (Fn + F5) refreshes the page.

Step 3. After refreshing, click the drop-down box under “Select edition” to choose the version that you need and click the Confirm button.

Step 4. After selecting the version, click the drop-down box under “Select the product language” choose a language that you need and click "Confirm". Then, you’ll be on the actual download page of the ISO file.

5. Click the "64-bit download" download button to download the 64-bit system ISO file.

After you download Windows 10 ISO files, you'll need to mount Windows.iso. To quickly mount an ISO file on Windows 10, you can follow the steps:

Step 1. Open File Explorer.

Step 2. Browse to the folder with the ISO image.

Step 3. Double-click the .iso file to mount it.

Notes:

If you need, AOMEI Partition Assitant has a "Migrate OS to SSD" feature to help you use extent Windows OS on the target PC without reinstalling. Besides, if you suffer data loss during the OS installation, you can also use AOMEI software to recover the lost data easily.