I am unable to update my windows to 8.1. I manage to download the update and begin to install it, then I am only able to get to 97% then update failed reverting changes. please can you help me.

Hello,

Please refer to steps mentioned here and see if they helps:

http://www.kapilarya.com/failure-configuring-windows-updates-reverting-changes

Hope this helps, Good luck :)

Hi r1990,

Are you updating to Windows 8.1 from Windows 8?

We could refer to the following link to update to Windows 8.1.
Update to Windows 8.1 from Windows 8
http://windows.microsoft.com/en-hk/windows-8/update-from-windows-8-tutorial

Please ensure the machine has got all the updates. We could run "Dism /Online /Cleanup-Image /RestoreHealth" to check the health of the system files.
Please unplug all the external devices before we try to update.

In addition, we could refer to the following link to have a troubleshoot.
"Failure configuring Windows updates. Reverting changes. Do not turn off your computer" error when you try to install Windows updates
https://support.microsoft.com/en-us/kb/949358

If the issue persists, please check the windowsupdate.log(search it directly) for detailed information to troubleshoot this issue. If you have troubles in analyzing the log, please upload them to OneDrive and paste the link here.

Best regards