Hi,
Thank you for contacting Microsoft Community.
I understand that you are getting Windows update error.
I will certainly help you with this.
By press Windows key+Pause/Break key to check if the Windows is activated after a clean install on system Window.
I would suggest you to go through below methods:
Method 1: Try to run the Windows update troubleshooter:
a. Press Windows key+R.
b. Type control and press enter.
c. Click on Troubleshooting.
d. On the left pane.
e. Click on view all.
f. From the list, click on Windows update.
g. Run the troubleshooter:
Method 2: Try to perform clean boot:
A clean boot is performed to start Windows by using a minimal set of drivers and startup programs. This helps eliminate software conflicts that occur when you install a program or an update or when you run a program in Windows 8.1, Windows 8, Windows 7, or Windows Vista. You may also troubleshoot or determine what conflict is causing the problem by performing a clean boot.
How to perform a clean boot in Windows
http://support.microsoft.com/kb/929135
Note: Refer "How to reset the computer to start normally after clean boot troubleshooting" to reset the computer to start as normal after troubleshooting.
Method 3: Try to check the cryptographic services.
a. Press Windows key+R.
b. Type services.msc and press enter.
c. From the list, right click on cryptographic service.
d. Click on properties,
e. Select the automatic in status type.
f. Click on start and click on apply and then ok.
Method 4: Refer the link below:
https://support.microsoft.com/en-us/kb/2714434
Method 5: Try to run the SFC scan:
https://support.microsoft.com/en-us/kb/929833
I hope this helps. Please let us know the results. Feel free to write us back for any further assistance with Windows, we’ll be glad to assist you.