Seen this before?
You may have received an error that says content blocked with category “none” when you try to access a certain website from within a firewall. I have seen this happen with BlueCoat firewall which is often used by very large companies to limit the sites that their computers can visit.
If you check at the bottom of your error message you may see a message like this SG:tpa-bcoat-3
bcoat means Blue Coat, and SG is their firewall software. In essence, their firewall has blocked your site because it does not know the category. I have not been able to find out how Blue Coat automatically sets their categories but it doesn’t mean our cause is hopeless.
There is good news!
There is a very easy way to fix this. BlueCoat Firewall allows you to suggest a category for a site and will review it.
Visit http://sitereview.bluecoat.com/sitereview.jsp to suggest your site. And usually within 24 hours your site will be accessible.
I used this to allow access to some of my personal resources and tips from my sites while within proxies of large companies.