I have exactly the same issue.
I work in IT and am convinced this is home hub related. Just to be clear, it cant be McAfee since I am using a Mac and dont have that type of AV on the machine.
The issue affects all my PC's and Mac's, it affects me if wired or wireless and i am using DHCP and static addressing.
I have tried different browsers with no improvement.
But hey .... soft reboot the router (or factory reset) and it works .... for a while then goes back to service unavailable.
I think there was a router software patch recently which has caused this.
When you do finally connect check when the router was last updated.