I have been seeing the same issue with the "Navigation to web page was cancelled" frequently over the past several days. It comes up when I am moving around on the Internet.
For example, I open IE9 which has Google as my home page, and enter something to search for. Randomly when clicking links from the results page I'll get the same screen as when an Internet connection has been lost but it has the "Navigation to web page has been cancelled" message. My IE is set to open new windows so I just close the error screen and still have the results page up. I can almost always click the same link again and it will work. Sometimes it will happen on a catalog page where i click an individual item to view it. I will get the navigation cancelled error, but like the results page, i can click again and it works.
At first I thought maybe my ISP was blocking some sites sites but when I looked at the results page the sites were OK per my Norton Internet Security and the names of several were sites I was familiar with and I knew they were safe. Then I remembered this is the first week that Comcast and AT&T are launching their '6 Strikes' spy software and all the telecoms have said they did not know what was going to happen with people's service. (I haven't noticed any change in download speed, but upload speed is down by 50 - 60% when I checked very early in the AM.)
The only things new to my system are I changed my ISP from Comcast to AT&t and I installed NIS 2013.
I am dumping Comcast so I'm losing the free Norton 360 they provided. AT&T offers McAfee which I don't like.
I have read a number of suggestions on dealing with this issue but almost none were Windows 7 and the applicable ones I did try haven't helped. Any ideas anybody?
OS: Windows 7 Ultimate 64 bit, Internet Explorer 9, both current in regards to updates.