What follows can be downloaded for ease of printing from:

Doing a Completely Clean (Re)install of Windows 10 Using Media Creation Tool to Fetch the Win10 ISO File

or

Doing a Completely Clean (Re)install of Windows 10 Using Media Creation Tool to Create Bootable Win10 Install Media on a USB Thumb Drive

depending on which set of instructions you prefer. Because I have experienced several incidents in the past where the Media Creation Tool completed downloading the ISO behind the scenes, but then died for some reason when creating the bootable USB drive, and since I could never locate the ISO I had to start all over again. This takes quite a bit of time if you are on a slow (read: DSL) internet connection. I personally prefer downloading the ISO file so that I know where it is and have it should I need it later. The choice, however, is entirely yours.

=============================================================================
Doing a Completely Clean Install of Windows 10 Using the Media Creation Tool to Get the Windows 10 ISO File

NOTE: If you want to be absolutely certain that only the existing Windows operating system disk can be selected when doing a reinstall, disconnect all other drives, internal or external, except your USB installation drive, prior to starting. This is not a bad idea, anyway, as it eliminates the potential for selecting the incorrect drive when using the diskpart command, below.

1. Download the Windows 10 Media Creation Tool (MCT) from the Windows 10 Download Page. You can snag the MCT by activating the Download Tool Now link (which looks like a button, but isn’t).

2. Run the MCT and choose the option to download media for another computer. The MCT defaults the language and architecture to match that of the machine running the tool. If you need to change either one for your target machine then uncheck the checkbox that controls this and tweak the dropdown for language and/or architecture [32-bit or 64-bit] appropriately. When you arrive at the dialog that prompts for what you want to download, elect to download the ISO file rather than to create a USB flash drive. I say this because if the flash drive creation fails for any reason you lose access to the ISO that was downloaded behind the scenes to create it. If you download the ISO file then if the creation of the bootable media fails you have it right there to try again.

3. Use Rufus (or a similar utility of your choosing) to burn the ISO to a flash drive to create bootable media. The following lettered steps presume you’re using Rufus. Attach your flash drive and run Rufus. In the first dropdown box:

a) If you know your machine is newer hardware that uses UEFI as opposed to BIOS, select GPT partition scheme for UEFI. If the machine originally came with Windows 8 or Windows 10 this is definitely the choice to make.

b) If you know your machine is older and uses BIOS, or are uncertain as to whether you have BIOS or UEFI, select MBR partition scheme for UEFI or BIOS. Virtually all machines that came with Windows 7 (and earlier Windows) were produced with BIOS and use MBR partitioning.

Leave the other checkboxes checked or unchecked with their defaults.

4. Find the Create a bootable disc using checkbox and make sure that the option ISO image is selected from the dropdown next to it. Just beyond that dropdown is the Click to select an image . . . button. Activate it and you will be presented with the standard Windows browse dialog that lets you locate and select the Windows 10 ISO file from wherever you saved it.

5. Activate the Start button. The ISO image will now be burned to the flash drive as bootable.

6. Boot your system from the USB flash drive. [Since I don’t know what UEFI or BIOS you’re using it’s up to you to find out how to change the boot device order on your machine to put the USB drive first in the boot order].

7. If this is a fresh install on a machine that has never had any operating system on it, and you are not using a drive that’s previously been used elsewhere, you can skip this step and move along to Step 8. Otherwise, when you get to the screen that asks for language, press Shift + F10 (or the Applications/Context Menu key if your keyboard has it) to open a Command Prompt or PowerShell session (depending on how your system is configured). Type the following commands:

diskpart (you will likely get a UAC prompt for diskpart, answer, “Yes,” of course)

list disk

select disk X
Where X is the disk number on which you wish to install Windows 10.
This is usually 0, as that’s what’s used as the default boot drive number on most systems.
That being said, make absolutely sure you have the correct number as the next step will wipe the disk of all partitions.

clean or clean all Purges the disk of all existing partitions

IMPORTANT NOTE: The choice of clean versus clean all is based
on why you are doing the reinstall. If it’s for yourself or someone
else who will be keeping the machine, use clean. This clears the
drive of all existing partitions, but does not literally wipe the drive
by overwriting its existing contents. A clean all also overwrites
drive’s contents, and takes much, much longer to complete as a
result. Count on approximately 2.5 hours per 500 GB capacity on
a HDD, at least. It could be longer. I only use clean all when the
machine is being donated or given to someone else and you
need to be absolutely certain that there is no way to recover
the data that was on the drive.



convert gpt Initializes the disk as GPT required for booting on a UEFI motherboard. If you get an error ignore it.
If and only if you know you have a legacy system that uses BIOS, use convert mbr instead of convert gpt.

exit (to close diskpart)

exit (to close Command Prompt or PowerShell)

8. The install will now continue; answer any prompts appropriately. When you get to the screen asking on which disk you wish install Windows, activate the Next button. The Windows 10 installer will automatically partition and format the drive (using the boot type you previously specified in the convert command above if you needed to perform Step 7, otherwise it will figure things out as part of the install to an uninitialized drive based upon the hardware configuration you have).

Important: If you get through the install to where you’ve answered “Custom” (which is your only choice for a completely clean install, as you’ve wiped anything that previously existed and cannot choose to work on an existing installation) you can walk away and let the install complete. BUT, be aware that because you’ve changed the boot order, after the install completes successfully the system will reboot from the USB thumb drive, which makes it look like you’ve circled right back to where you started. You haven’t, really, just remove the USB drive, restart the computer, and as part of that get back in to UEFI/BIOS and change your boot order such that your HDD/SSD is the first boot device.


=============================================================================

Doing a Completely Clean Install of Windows 10 Using the Media Creation Tool to Create a Bootable USB Drive


NOTE: If you want to be absolutely certain that only the existing Windows operating system disk can be selected when doing a reinstall, disconnect all other drives, internal or external, except your USB installation drive, prior to starting. This is not a bad idea, anyway, as it eliminates the potential for selecting the incorrect drive when using the diskpart command, below.

1. Download the Windows 10 Media Creation Tool (MCT) from the Windows 10 Download Page. You can snag the MCT by activating the Download Tool Now link (which looks like a button, but isn’t).

2. Run the MCT and choose the option to download media for another computer. The MCT defaults the language and architecture to match that of the machine running the tool. If you need to change either one for your target machine then uncheck the checkbox that controls this and tweak the dropdown for language and/or architecture [32-bit or 64-bit] appropriately. When you arrive at the dialog that prompts for what you want to download, elect to create a bootable USB flash drive.

3. Boot your system from the USB flash drive. [Since I don’t know what UEFI or BIOS you’re using it’s up to you to find out how to change the boot device order on your machine to put the USB drive first in the boot order].

4. If this is a fresh install on a machine that has never had any operating system on it, and you are not using a drive that’s previously been used elsewhere, you can skip this step and move along to Step 5. Otherwise, when you get to the screen that asks for language, press Shift + F10 (or the Applications/Context Menu key if your keyboard has it) to open a Command Prompt or PowerShell session (depending on how your system is configured). Type the following commands:

diskpart (you will likely get a UAC prompt for diskpart, answer, “Yes,” of course)

list disk

select disk X
Where X is the disk number on which you wish to install Windows 10.
This is usually 0, as that’s what’s used as the default boot drive number on most systems.
That being said, make absolutely sure you have the correct number as the next step will wipe the disk of all partitions.

clean or clean all Purges the disk of all existing partitions

IMPORTANT NOTE: The choice of clean versus clean all is based
on why you are doing the reinstall. If it’s for yourself or someone
else who will be keeping the machine, use clean. This clears the
drive of all existing partitions, but does not literally wipe the drive
by overwriting its existing contents. A clean all also overwrites
drive’s contents, and takes much, much longer to complete as a
result. Count on approximately 2.5 hours per 500 GB capacity on
a HDD, at least. It could be longer. I only use clean all when the
machine is being donated or given to someone else and you
need to be absolutely certain that there is no way to recover
the data that was on the drive.



convert gpt Initializes the disk as GPT required for booting on a UEFI motherboard. If you get an error ignore it.
If and only if you know you have a legacy system that uses BIOS, use convert mbr instead of convert gpt.

exit (to close diskpart)

exit (to close Command Prompt or PowerShell)

5. The install will now continue; answer any prompts appropriately. When you get to the screen asking on which disk you wish install Windows, activate the Next button. The Windows 10 installer will automatically partition and format the drive (using the boot type you previously specified in the convert command above if you needed to perform Step 4, otherwise it will figure things out as part of the install to an uninitialized drive based upon the hardware configuration you have).


Important: If you get through the install to where you’ve answered “Custom” (which is your only choice for a completely clean install, as you’ve wiped anything that previously existed and cannot choose to work on an existing installation) you can walk away and let the install complete. BUT, be aware that because you’ve changed the boot order, after the install completes successfully the system will reboot from the USB thumb drive, which makes it look like you’ve circled right back to where you started. You haven’t, really, just remove the USB drive, restart the computer, and as part of that get back in to UEFI/BIOS and change your boot order such that your HDD/SSD is the first boot device.