tserv1.den1.he.net seems to be down for me. My endpoint is 184.105.250.46. I've tried pinging that IP from multiple locations and online ping tools and I'm not receiving any replies back. The TunnelBroker status page though shows tserv1.den1 as up though. Not sure what else I can do at this point.
Got a response back from HE support:
We have experienced a hardware failure at the Denver site. A tech has been dispatched with replacement equipment. The estimated repair time is roughly 5 hours.