Fix Activation Problems After Upgrade:
If Windows 10 can not be activated after an upgrade, the error is not due to your key, but Microsoft's servers. These servers are very busy after the big rush to the new operating system.To activate your copy of Windows, click the bottom left of the Windows icon and choose the "Settings".
In the category "Update and Security", click on the tab "Activation".
Here you click on the button "Activate" and wait until the process is complete.
If an error message appears, just try it again. In the test, it worked for the fifth time. Alternatively, you can wait a few days and start the activation again.
If this approach does not work after a few days, you can activate Windows via the command prompt:
In the Windows Search box type "cmd" and click with the right mouse button on the same program.
In the context menu select "Run as administrator".
In the command prompt, type the command "wmic path SoftwareLicensingService get OA3xOriginalProductKey" and confirm with [Enter].
Your current Windows Key will appear, highlight and copy it with a right click.
Now enter the command "SLUI 3" and paste the newly copied Key in the field.
Enter "SLUI 4" and follow the instructions on the screen to activate Windows 10 by phone.
Create activation file to resolve error code 0xc004f034:
If the above steps do not resolve the error, create a .BAT activation file in Notepad. Run it to get your Windows 10 activated. Follow the steps below:Log into Windows 10 with Microsoft Account that has administrative rights.
Right-click on the desktop and create a .txt file. Name it ActivateWindows10.txt
Open the file and post the following into Notepad:
@echo off
:loop
cscript /nologo slmgr.vbs /ato
if errorlevel 0 goto end
goto loop
:end
echo Activation was successful. Press any key to close this window.
pause>nul
exit
Save the file in .BAT format as Windows10Activation.BAT.
Now click on the file to run the script.
Check if your Windows 10 is now activated.