So recently made the switch to X1, and received a shiny DPC3939. As the wi-fi power is better than my existing router (which used to live between the Comcast modem and the rest of my network), my existing router is no longer on the network. In order to save myself some hassle, changed the "Local IP Configuration" ip address to 192.168.1.1 to match what my old wifi router was set up for.
Now I've been using IPv6 on Comcast for a while, so I saw no reason to disable it. Until I tried to reach my DPC3939 at it's new 192.168.1.1 address. And Cannot. Almost everything else works perfectly: I can go out to the internet and play games, watch YouTube, NBCSports for my hockey, etc. EXCEPT: tv.xfinity.com times out. AND I cannot reach my router on the old 10.0.0.1 address either.
I CAN acces my router using http://[ipv6 address]. Thankfully.
Tried calling support, couldn't get anyone to explain the problem. Anyone here have a clue?
Solved! Go to Solution.
Okay, so not entirely fixed. Yesterday I could do everything, today I cannot get tv.xfinity.com to respond. looks like a TLS handshake with tv.xfinity.com is failing. This forum post looks like it's trying to handshake with polaris.xfinity.com and failing also.