Making second site accessible?

Norton Security | Norton Internet Security
1

"Firefox can’t establish a connection to the server at ad.doubleclick.net.

    The site could be temporarily unavailable or too busy. Try again in a few moments.
    If you are unable to load any pages, check your computer’s network connection.
    If your computer or network is protected by a firewall or proxy, make sure that Firefox is permitted to access the Web."


The above was checked via Firefox only to discovcer that I got the same message on Mocrosoft Edge, and Opera Browser. I believe that the cause must be in Norton. Any suggestions?

Lifelock

2

Firefox can’t establish a connection to the server at ad.doubleclick.net.

That would actually be a good thing for me. As bjm_ notes that site is for ad tracking, and no one really wants that.

 

3

Sounds like your browsers are blocking tracking cookies / Ad Tracking. 
Maybe, a browser extension or browser tracking prevention or global ad block program.  VPN?

What are blocked website URL?