Here's the deal. Comcast allows me to log in at my work and access HBO GO, no problems whatsoever.
When I am at home, I am not able to even pull up the log in page for Comcast. When HBO GO redirects me to log in at Comcast the page just times out. This just started happening this week, I've been logging on and accessing HBO GO and Comcast from home for over a year.
Here's what I've tried so far: Clearing my cookies, restarting the computer, restarting the modem/router, using ie and mozilla. None of these work. Anytime, from home, that I try to log in to comcast, the page times out.
go to tools options in internet explorer and choose reset to defaults. See if that works. check in the sites that you are blocking in your browswer. its obviously something on your home pc and not something on the other end as it works at your job.