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Any Ideas on a Comcast Issue that Only Effects Firefox?

jamesjibbity
jamesjibbity
more options

Some background....

For the last few years, Comcast has offered a "Domain Helper" service for Comcast users that use Comcast's DNS servers. When enabled and a DNS lookup fails, instead of seeing the browser's "can't connect" message, the browser gets directed to Comast's "Domain Helper" search.

Luckily, Comcast allows their users to opt-out (turn off) this service. I opted out in 2009 and haven't thought about it since... until yesterday.

Yesterday, I typo'd a web address (as I do daily) but, instead of the Firefox "Server Not Found" message with the "Try Again" button, I was sent to Comcast's Domain Helper.

The first thing that came to mind was that Comcast reset my settings so I logged in to my account but my Domain Helper setting was still set to disabled.

I then tried the same typo'd domain in Chrome. No Domain Helper, just the expected error message from the browser.

I then tried the same typo'd domain in Safari. No Domain Helper, just the expected error message from the browser.

I then tried the same typo'd domain in MSIE. No Domain Helper, just the expected error message from the browser.

I then tried my 2 laptops (same network, different OS's, same version of Firefox) and had the same results (Comcast's Domain Helper is only displayed when using Firefox).

Just to make sure, I overrode Firfox's User Agent string to see if that would change anything. It did not.

Confirming the issue is related to Comcast's DNS is easy since it stops when switching to OpenDNS or Google's DNS. But this just makes it more curious.

So, Im wondering....

Any other Comcast users (I'm in Atlanta, GA) experiencing this?

How could this only be effecting one browser? Is it possible for a DNS Server to send back different responses based on browser?

Has anything changed with the way Firefox 8 handles domain resolution? I'm not sure this started with the update but it never happened with earlier versions of Firefox.

As you'd expect, Comcast's support is clueless and give the same useless suggestions they give whenever they're presented with a problem that doesn't appear on their sheet of scripted resolutions. Restart your router, clear your cookies and cache, restart you computer, reinstall Firefox. Bleh.

Anyway, I know some sharp people hang around here as well as some people that may be familar with how Firefox handles DNS lookups so I figured I post this here. Like I said, it's easy to fix on my end (change my DNS servers) but not knowing really bothers me.

Some background.... For the last few years, Comcast has offered a "Domain Helper" service for Comcast users that use Comcast's DNS servers. When enabled and a DNS lookup fails, instead of seeing the browser's "can't connect" message, the browser gets directed to [http://search3.comcast.com/?cat=dnsr&con=ds&url=ahkjfhakjsdhakjshd.com Comast's "Domain Helper" search]. Luckily, Comcast allows their users to opt-out (turn off) this service. I opted out in 2009 and haven't thought about it since... until yesterday. Yesterday, I typo'd a web address (as I do daily) but, instead of the Firefox "Server Not Found" message with the "Try Again" button, I was sent to Comcast's Domain Helper. The first thing that came to mind was that Comcast reset my settings so I logged in to my account but my Domain Helper setting was still set to disabled. I then tried the same typo'd domain in Chrome. No Domain Helper, just the expected error message from the browser. I then tried the same typo'd domain in Safari. No Domain Helper, just the expected error message from the browser. I then tried the same typo'd domain in MSIE. No Domain Helper, just the expected error message from the browser. I then tried my 2 laptops (same network, different OS's, same version of Firefox) and had the same results (Comcast's Domain Helper is only displayed when using Firefox). Just to make sure, I overrode Firfox's User Agent string to see if that would change anything. It did not. Confirming the issue is related to Comcast's DNS is easy since it stops when switching to OpenDNS or Google's DNS. But this just makes it more curious. So, Im wondering.... Any other Comcast users (I'm in Atlanta, GA) experiencing this? How could this only be effecting one browser? Is it possible for a DNS Server to send back different responses based on browser? Has anything changed with the way Firefox 8 handles domain resolution? I'm not sure this started with the update but it never happened with earlier versions of Firefox. As you'd expect, Comcast's support is clueless and give the same useless suggestions they give whenever they're presented with a problem that doesn't appear on their sheet of scripted resolutions. Restart your router, clear your cookies and cache, restart you computer, reinstall Firefox. Bleh. Anyway, I know some sharp people hang around here as well as some people that may be familar with how Firefox handles DNS lookups so I figured I post this here. Like I said, it's easy to fix on my end (change my DNS servers) but not knowing really bothers me.

All Replies (1)

the-edmeister
the-edmeister
  • Moderator
more options

I use Comcast in the Chicago area market and have a problem with the "Opt Out" stopping about once a year or so. It appears as being enabled at the Comcast Opt Out page, but the unresolved addresses are still going to the DNS "domain helper" service.

What works for me is to turn off the opt out preference, log off from that Comcast account, and close Firefox. When I restart Firefox, log in to Comcast, and then set the pref to "opt out" again - it works as intended and doesn't cause me a problem until it happens like 10 to 12 months later.

As far as why it seems to affect browsers in a different way, I have no idea. I do have Safari, Opera, and IE 8 installed, in addition to multiple versions of Firefox, but I don't use those other browsers enough to have seen a difference. I am usually opening pages from within Firefox in those other browsers to view the difference, or to print something that Firefox screws up in the Print Preview.

Modified by the-edmeister