Windows 10: Problem with activating Windows 10

I`m running Windows 10 as a bootcamp on my MacBook Pro. Last month my MacBook broke down and the support had to delete everything on the Mac, included my Windows 10. I have downloaded and installed Windows 10 again on my Mac, but now i have trouble with activating Windows 10 again with the same productkey that i used last time. I get this code 0xC004C020 which says that the productkey is already in use, but thats not the case. Does anyone of you know how i can reactivate windows using the same prodcutkey?

Thanks.

:)

 

Windows 10 Activation (Insider)

How long did you wait for activation?
When I re-installed with a fresh install... it took a few hours to sync and activate.
However, it did, finally, activate.

 

DOWNLOAD WINDOWS 10 NOW - Upgrade and ISO direct from microsoft

Click to expand... Yeah I went to that site, why do I need to buy a key?
I won't buy a key, stupid.

I'll revert back to windows 7 then.

When I still was on windows 7, about a year ago I added 4GB extra ram which is a total of 8GB now,
is that causing the problem?

 

Windows 10 Tweaks

Pressing “Windows+Pause Break” (it’s up there next to scroll lock) opens the “System” Window.

Windows 10: In the new version of Windows, Explorer has a section called Quick Access. This includes your frequent folders and recent files. Explorer defaults to opening this page when you open a new window. If you’d rather open the usual This PC, with links to your drives and library folders, follow these steps:

• Open a new Explorer window.
• Click View in the ribbon.
• Click Options.
• Under General, next to “Open File Explorer to:” choose “This PC.”
• Click OK

credit to Lifehacker.