Windows 10: Problem with activation of Windows 10

I have a problem regarding the activation of Windows 10 in my PC. Recently, a tab appeared on the screen asking to activate windows. But I ignored it considering it as a mistaken message. But now in my pc, at the down rightside corner, a phrase, 'Activate Windows' appears whenever I switch it on. When I go to the settings to solve the issue, and select the first option 'troubleshoot', it says contact your administrator. Then there is the second option, 'Change Product Key'. I don't know the product key, so I get it from Windows Powershell. But whenever I type that product key, it says error. Few months back, some hardware parts of my PC were replaced, during the time it was given for repair at a nearby gadget store. I don't know if I'm experiencing this problem because of this.


Also the error code that appears at the troubleshoot option is 0xC004F074.


So kindly help me to activate Windows 10 in my system, and to retrieve my Windows Product Key.

:)

 

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.