My Lenovo windows 10 keeps trying to install updates but continues to say "Failed to complete updates" "Undoing updates". Could it be that Norton 360 is preventing it from installing and completing the updates?
Windows 10 cannot complete updates
This is a known fault with Windows 10 (and some other versions) affecting certain cumulative updates for Windows.
Do try the troubleshooter suggested since Microsoft know about the problem and have fixed it for some versions.
If no luck post again since there are some alternative sources of Windows help I may be able to help you with.
To add to Krusty's comment re the Windows Update Troubleshooter, have you also done a full RESTART ?
Also suggest disabling Fast Start Up if enabled may help.
It is unlikely Norton is causing this. Have you ran the Windows Update Trouble Shooter?