I started getting this error recently and was almost to my wits end! I read other comments in the "Blog" and did almost everything others had done until..."In Chrome I turned off ALL my extensions" and tried to access my Norton's account again. What do you know, "Bobs Your Uncle", I was able to access my account once again!!! So, from that point I started troubleshooting to see if it was just the extensions or a particular one. Well...found out that my "password manager" extension was the problem. Others on the forum/blog has indicated that Dragon Speaking Naturally was their problem which might also be true, but in my case I wasn't using that application. So, my suggestion at this point to others would be to turn off ALL extensions in Chrome and see if that fixes it. If it does, then turn them on one at a time and try to access your account until you find the extension that is giving you the problem. Hope this helps someone!!!