What is this?

Everytime I go to a website it redirects me to http://actsvr.comcastonline.com
some websites such as this work, I ran the I am customer and put my number in one time it worked but now it gives me a 404 error each time I put my number in. I called comcast and they told me to disable my antivirus while running it which I did, and still no luck..I ran a program called combofix and it fixed something like MSN working. Really strange, I don't think it's a virus because it stopped working when my cable got turned on again..