Windows 10: Re-installing Windows 10

I just installed a copy of Windows 10 home on a new computer but unfortunately the product key that came with it is invalid and so I can't activate it. After a lot of research it turns out I'm going to have to purchase another copy of Windows 10 home and install it "on top of" the old one.

How is this done? If I download the new copy from Microsoft how do I get it installed when I already have an un-activated copy on my computer?

Windows settings is telling me that my current product key is invalid and to solve it I can purchase a "genuine" copy from the Microsoft store. Will the new copy install normally even though it's already on my computer? Are there any special instructions for this? Will I have to format my C: drive to install a new copy of Windows 10?


Thanks for any help

:)

 

windows xp installation and dual core am

could someone please list the steps they follow to install windows with a dual core processor and windows xp service pack to. I'm reletively new to amd dual core and i feel i'm missing a step. All help will be appreciated. thanx

 

Is it time for Windows 10 already?

Here's a good step by step guide on doing a fresh install.

How to clean install Windows 10 from a USB drive - Software - Feature - HEXUS.net

 

Installing Windows 10 on New PC?

I'm going to be building a new PC on Christmas and want to install Windows 10 on it. I have Windows 10 on my current PC, which I installed upgrading from 8.1 with the files on a USB. How do I go about installing a clean copy of Windows 10 on this new PC? I think I recall something about installing it once makes Microsoft recognize your hardware, but since this will be a PC I'm not sure what steps I need to take. Do I need to go 8.1 -> 10 or is there a method of going directly to 10?