Windows 10: Why Cant I Activate W10, and How Do I Solve This?

I apolgise in advance for the lengthe of this post, but hope the initial detail will help prevent wasted time later.


On My Original PC:
I built this PC about 5 years ago and purchased and installed W7.
3 months ago, I wanted to upgrade from W7 to W10, so at the MS-download-page, I entered my W7 Product Key and downloaded the free W10 upgrade.



Then I did a Custom Install of W10 in a new partition of this PC.
I had to do this several times as I had problems getting it to install correctly, which I think was caused by an incorrectly formatted HDD, but I eventually got it installed, I tested it and it worked OK, but I did not activate it.


I continued to use W7 for a few weeks, and then my PC failed, and I had to rebuild it with a new Mobo,CPU etc.

During this time, I needed a PC to be able to fix my failed PC, so I had to install W7 on my old XP PC.



So now, I need to change over to W10, so I'm trying to activate it:



My W10 Activation Page has this red error message at the top:
'We cant activate Windows on this device because you don't have a valid digital licence or product key.
If you think you do have a valid licence or key, select Troubleshoot below. Error code: 0xC004C003'


...clicking its link: Troubleshoot

...displays a blue popup that says:
'Troubleshooting has completed, we weren't able to activate Windows on this device.'

I clicked its link: I recently changed hardware on this device


...and a grey popup says: Unable to activate Windows
'We can’t find any devices linked to your Microsoft account that can be used to reactivate the device that you’re using at the moment. Make sure that you’re signed in with the same Microsoft account that you linked to the Windows 10 digital licence on this device, or try again later.
Link:>See other devices linked to your Microsoft account<



I clicked the above link, and popup says:
'Reactivate Windows 10:
We can’t reactivate Windows from these devices.' Link: >Learn more<



...and below this it says:
'...If you can’t see your current device, (in the above list) make sure that you’re signed in with the same Microsoft account that you linked to the Windows 10 digital licence on this device. '



All Very Confusing:
Microsoft Account / User Account / email account / Product Code / Digital Licence !!!



I don't know when or how I was supposed to:
a: Create a: Microsoft account
and b: Link it to the: Windows 10 digital licence on this device



When I did the W10 install, as usual, I entered a user-name & password
(eg: those that you have to enter when you boot up Windows)



Now, after several days of going round in circle (somehow) I was forced to create or open an account (Microsoft Account?)
which I did by inserting an old 'hotmail' email address.

NOW: When I boot up, I have to sign in using that 'email address, as my user account' and its password.



And on this page: Start/Settings/Accounts
...it says that, I'm logged in as: as Administrator via that 'hotmail email address'



At: Task Manager/Users
This used to show my original: user-name & password
But now it just shows this: hotmail email address

Q: So why, and how do I get my original login, user-name & password, back?



And on this page: Start/Settings/Email & Accounts
It says that my 'Microsoft Account' is that hotmail email address.



And on this page: Start/Settings/Your Info
Clicking on: Manage My Microsoft Account
Opens a MS webpage, which shows my current PC-ID & mobo



Next, on the 'Activation Page'
I clicked its link: Change Product Key
I entered my W7 Product Key.
Again its says:
'We cant activate Windows on this device because you don't have a valid digital licence or product key.
If you think you do have a valid licence or key, select Troubleshoot below. Error code: 0xC004C003



So I checked the meaning of that Error code: 0xC004C003
Which says:
'You may see this error because the Windows 10 product key you entered isn’t valid.
Product keys are unique—assigned to a specific user to install on a single device.
If a key was used (or attempted to be used) on multiple devices, it’s marked as not valid.
To activate Windows, you’ll need to provide a different Windows key unique to your device.'



So why is my product key no longer valid?
As mentioned above:
I had several failed W10 installs, and when my original PC failed,
I needed a PC to be able to fix my failed PC, so I had to install W7 on my old XP PC.

If that is the cause, it seems crazy and very unfair that I'm not allowed to reinstall W7 software that I have paid for!


So how do I solve this W10 Activation?
Why should I have to buy a new licence for this free W10 upgrade ?
when I have not done anything wrong?!



NB: I followed the various links to page after page of info, that appear from time to time,
but none of that info leads to any solution, you just go round & round in circles.



Any advice appreacited.

:)

 

W10 activation and motherboard failure.

Hey, wasn't sure what section to put this in.

Motherboard died yesterday, managed to source a replacement but I believe I am correct in thinking that once I swap the board W10 will deactivate itself and demand I buy a new copy?

If so, would I be able to get around this by booting the system with a spare HDD, installing W7/8, upgrading to W10, then connecting the original drive (so the MB has been used/activated with W10)?

Thanks.

 

Cannot activate w10 after reinstalling W10 error 0xC004F034

I had to reset w10 when I was trying to solve the AMD Window driver problem caused by the faulty w10 1703 upgrade problem.

Now my laptop insists that I activate w10.

• It says I have w10 home installed.
• It says "We can't activate windows on this device right now.....Error code 0xC004F034
• Troubleshooter says it found a digital licence for this devise running w10 home (because this PC had a free update from w8) . To activate using this licence you need to install w10 home

Except w10 home is already installed!!!!!

I have tried "I Changed this device hardware recently". It asks me to log in but then says "Opps something went wrong... we can't add your Microsoft account to this device right now" even though I am logged in with that username.

So am stuck!

Basically, since that irritating w10 upgrade problem with 1703 that messed up attached screens on AMD devices, I have not been able to use this laptop.

Please help.

 

Important W10 activation key questions left unanswered by Microsoft

Yup! I saw it in there this morning. I really like this new activation route they have gone so far. Super easy to maintain.