I just tried something different. I cleared the cache and dumped all cookies. Did a CTRL+F5 on all three browsers (IE, FF, Chrome) and still couldn't get through. Tried Ipad and Samsung tablet. Tried phone. All without any luck.
Then I turned off the wifi on my phone and used my AT&T connection. It opened immediately. If you are a Mediacom customer, could you please try to open this link: https://forums.mediacom.com
I am a Mediacom customer. I tried the above link and it failed. Windows said it did not recognize "forums.mediacom.com". I don't know if this helps or not. It also said to contact the provider.