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Not sure why this isn't working right... (IPv6/DPC3939)

Frequent Visitor

Not sure why this isn't working right... (IPv6/DPC3939)

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?

 


Accepted Solutions
Frequent Visitor

Re: Not sure why this isn't working right... (IPv6/DPC3939)

The solution was to factory reset the modem and reconfigure everything.


All Replies
Problem Solver

Re: Not sure why this isn't working right... (IPv6/DPC3939)

Have you tried rebooting your DPC3939? You can do it from the app, GUI, or unplug it for a minute and plug it back it or a press and release of the reset button.
Frequent Visitor

Re: Not sure why this isn't working right... (IPv6/DPC3939)

Unfortunately, yes. Even did a full 5 minute power cycle.

Problem Solver

Re: Not sure why this isn't working right... (IPv6/DPC3939)

Try holding the reset button for 30 seconds. This will trigger a factory reset. Then try doing it again.
Frequent Visitor

Re: Not sure why this isn't working right... (IPv6/DPC3939)

Wouldn't the "Restore Factory Settings" button in the router admin do the same thing?

Frequent Visitor

Re: Not sure why this isn't working right... (IPv6/DPC3939)

jweaver: thank you, the factory reset resolved the issue.

Frequent Visitor

Re: Not sure why this isn't working right... (IPv6/DPC3939)

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.

Frequent Visitor

Re: Not sure why this isn't working right... (IPv6/DPC3939)

The solution was to factory reset the modem and reconfigure everything.