"One more step to access......"?

it's a joke

It said "One more step to access <insert pornsite name here>
There are easier ways to get to those sites than using scareware. No worries for you. SG has some of these ads too. They just say this to every user and want to scare him. Then you should download that "virusscanner" for 100€ that is downloading more shit.

Your IP is blacklisted somewhere. This is usually caused when you have a dynamic IP, and inherit a previous spammer / hacker's IP. Reset your modem or talk with your ISP.

Sounds like you have a case of adware. Check your browser proxy settings and run MBAM.

Kaspersky and avira are jokes, delete them off your computer, get emsisoft anti malware, and malaware bytes, and spybot search and destroy, its all you will ever need and they are all free to use.

those 3 combined = captain planet

they are gods when mixed together.

sometimes just for fun throw in a housecall virus scan.

I'm seeing a lot of total bullshit in this thread.

That warning you seen, is official. It is from a server hosting tool called Cloudflare, which is meant to help prevent DDoS attacks. As these DDoS attacks can use botnets, which make use of infected computers to bring down a site by sheer volume of traffic, it has triggered the DDoS protection, and wants to stop it. The site you are trying to access, is probably experiencing a DDoS attack of some kind, or maybe a false-trigger by a large amount of volume. The important thing is, is that it's a general warning that near everyone will experience when trying to access that site at that time. It doesn't mean your computer is infected, but it likes to make sure. Cloudflare works by making it so that your traffic won't reach the site, until you've entered that captcha, theoretically stopping a botnet attack.

TL;DR - No need to worry, enter the Captcha, wait for the site to get it together again.