Microsoft has been delivering Windows 10 upgrade installation files onto Windows 7 and 8 machines – even if the user has not selected to upgrade to Windows 10. This causes long downloads, significant bandwidth usage, and long system shutdowns (the upgrade files are gigabytes in size and apply updates).
The update named KB3035583 has already been installed on your machine. EVEN if you have NOT chosen to reserve your Upgrade!
Follow the instructions here:
You also need to follow the instructions fully including the link in the middle of the page:
You MUST restart your machine and recheck updates and wait for this to appear again to hide it.
There is another site here that has additional information on additional updates that are “prepping” your machine even if you have not reserved your “upgrade”
Please be aware that normally we encourage users to update and apply updates on a regular basis.
This information is being promoted for those who do not want the additional bandwidth consumption or nagging upgrade preparation files forced upon them.