updated 2019
W10 clean install
-- windows key --
You might want to remember your original windows key, just in case.
If needed, the original key should be used, but normally the UEFI bios remembers it.
If you upgraded to Windows 10 for free from Windows 7 or Windows 8.1, you should have a digital license instead of a product key.
You can download "showkey plus" from here, unzip it and run it.
link to showkey plus
It should show both the original key and the default w10pro key VK7JG-NPHTM-C97JM-9MPGT-3V66T.
-- creating w10 media --
microsoft has some instructions and download here:
link to w10 media creator
Download the tool (is only 19MB)
Also click on "Using the tool to create installation media (USB flash drive, DVD, or ISO file) to install Windows 10 on a different PC (click to show more or less information)" that explains what to do:
Run the tool, it will make an install usb or dvd with the newest w10 version.
It is fastest with USB (8GB usb stick is needed)
Using the tool to create installation media:
- Select Download tool now, and select Run. You need to be an administrator to run this tool.
- If you agree to the license terms, select Accept.
- On the What do you want to do? page, select "Create installation media for another PC", and then select Next.
- Select the language (only 1 language can be chosen), edition (choose w10 pro), and architecture (64-bit) for Windows 10.
-- wiping harddisk with Paragon --
If you have this phantastic tool, boot Paragon HarddiskManager from usb - it starts a win-PE environment
If asked for network, say no
When started, click "security and optimisation"
in the wizard, select C:\
Wipe method > "select your own standard" (do NOT choose the default military grade super wiping method, because that will take several hours and can damage your harddisk if it was a bit old.) > next.
In the custom page, use its default settings with 1 pass > next
-- installing from created media --
Boot from the usb
NBNBNB When asked to login with MS account, DON'T.
Instead, click the "offline account" in the lower left corner.
It will ask one more time in the next screen, but don't use MS login and don't use Windows Hello !!! (otherwise you can only use the pc when online, and with several passwords!!)
Also, when asked for a password, just only ENTER (this means a blank password)
The next bunch of screens ask about some features -> Always answer NO or Don't or NO !
Some more info is found on the same microsoft page, under:
"Using the installation media you created (click to show more or less information)"
and
"Additional methods for using the ISO file to install Windows 10 (click to show more or less information)"