Hello,
This is just to report a possible bug to Norton folks!!
I was getting the error (see my subject line) and after digging, I figured out that your software has a issue with my ReDirect statement in my Apache conf file, all worked OK after I removed my redirects. Norton need to allow for URL with / without WWW.
For example I wanted to verify the file http://onepossibility.org/nortonsw_eda139c0-6d9b-0.html
And my Apache was redirecting that to http://www.onepossibility.org/nortonsw_eda139c0-6d9b-0.html
Using
<VirtualHost *:80>
ServerName onepossibility.org
Redirect / http://www.onepossibility.org/
</VirtualHost>