Whereabouts are you and your ISP? I've been trying to look for solution under the same issue and can open any links but bnet related. Seems it has something to do with an with windows update(which i haven't) or bnet update conflicting with our ISPs.
Blizzard have had massive problems since attempting maintenance yesterday for all users from Australia (see here: https://twitter.com/BlizzardCS/status/616044503648985088), Canada, Spain and a few other countries. At first they thought it was with local ISP's, then actually admitted later it was an issue at Blizzard's end with the maintenance update and have been trying to fix it for over a day now.
They haven't advised of any fix date or time for anyone effected, other than to say they are working on it as hard as they can.