I recently changed my service from phone, TV, and internet, to internet-only. After the change, some (not all) of the computers in my home started re-directing to a comcast authentication page. URL follows:
I enter my account information, which it accepts, then it goes through some pages trying to "activate" some non-descript video devices. It eventually fails, and tells me to close my browser. Re-opening my browser brings me back ot the same page, and gets the same results. No software changes were made to the computer experiencing this issue, and both Firefox and IE give the same result.
I tried connecting one of the computers experiencing the issue directly to the modem, but experienced the same problem.
I contacted comcast live chat support, and after about 3 hours they gave up and said they would send a tech out some time next week. I explained to them that I work from home, and am dependent on my network connection to do my job, but apparently 1 week is the fastest they can get someone out.
Any suggestions on why some computers might suddenly start re-directing to this xfinity page after I made changes to my service?
Too many people override the DNS servers on their DHCP lease, and this can cause all kinds of problems. Unless you have a specific problem with the ones provided on your DHCP lease, or know exactly what you're doing and why, do NOT use DNS overrides. A common problem is someone puts in an override several years ago for some reason and then never changes it, but the DNS server ip is now obsolete and causes trouble. Comcast knows what DNS servers are current should be used, so overriding them without a specific and CURRENT reason is a bad idea.
Internet access became non-functional when I use the DNS on my DHCP lease. Unless there is a way to get a good DNS from my router [edit: modem], I have no choice but to use an override. I'm not saying I want to have to use manual override (it's a PITA) but it's the only way that works.
What DNS servers are you getting in your lease? If you have a problem, it's best to describe it here and get it fixed. Those using routers tend to have more DNS problems because the DNS proxy setups in some routers are not very good and get cause bad DNS responses. Sometimes a firmware update fixes this, other times it's just best to get a better router. For example, if your computers draw a DHCP lease from the router and the DNS server is the router's IP address, then you're using a dns proxy setup. In other words, all DNS queries from your computer are sent to the router, which in turn queries the DHCP servers IT has setup and returns the response to the requesting computer. This two layer setup can be a problem if the DNS proxy is not doing things properly, which might cause the DNS server to reject the query, cause long delays, etc.
So give us the details and if there is an actual Comcast DNS problem, we can point the right people at it. If not, we might be able to help you resolve the issue.
Yeah, those are the wrong servers, they give out the same IP address for all queries which is how Comcast implements the modem self registration process (at least in part). I suspect something got tripped up when you got Triple Play, causing your cable modem registration to become buggered. My suggestion is to call Comcast and have them re-register your cable modem.
There have been no equipment changes in six months. And this problem just started this month. The set up on all systems is as they came originally with the auto detection during setup. What else do you need to know? I am a black box method type computer user, If you plug it in and it works you leave it alone.
Disconnect the router from the cable modem (not cable box).
Remove the cable modem's power cord and let it sit for a few seconds. Then plug it back in.
Wait for it to connect back up to Comcast (ie. the lights on the front stabilize).
Now connect the computer's ethernet cable to the ethernet port on the cable modem, and reboot the computer.
Any better? If so, the problem is the router config is using some odd DNS server. Simply reset it to factory defaults (see your router manual) and then reconnect the router like above, power cycling the modem before you hook the router back up.
If you still have a problem, post the output of ipconfig /all from the computer.
This procedure from Baric worked well in stopping the re-direct of the Self Activation page from popping up since exchanging my modem. Several calls to Comcast tech were of no help. I kept calling them hoping to find someone who might know what I was talking about. They all tried there standard procedures, unplug, reset, re-boot, clear browser, etc. One tech wanted me to un-install IE9 and re-install. Since I also use Firfefox I passed on this suggestion. Thanks Baric for your helpful solution.