To clarify, it was the Norton program that suspected a problem and closed off access to the internet. But without internet access, I couldn’t enter my password for Windows 10, thereby effectively locking me out of my computer in my case. I was able to access some basic functionality to try and repair the issue. In retrospect it’s probably better I didn’t attempt any repairs or setting restore points (none of the options were operational as it turns out) because I didn’t lose any programs, files, internet favorites, etc. Hope it helps.

December 2017. My personal computer couldn’t access the internet after the latest Windows 10 update. I thought it might have been the update itself causing the problem. After a few days of working with 3rd party technicians to try to solve it, I brought my computer in to a Microsoft store. They diagnosed it free of charge and were able to override the Norton anti virus software that had kicked in and locked me from my computer. I hope this helps others. Happy new year.