Could not visit,, yahoo mail and login page

My computer background info:

Windows XP SP2. Using Comodo Internet Security Premium (5.9.221665.2197) Virus def: 11477. A few months ago, installed the Comodo Dragon browser out of curiosity.


The morning of February 9, 2012 using FireFox, I could log into to read and send email. And, could visit other websites without issue. However, in the evening using FireFox, could not access the login page for I got an error message about the server (error 108; unfortunately, I did not write the error message down). But, otherwise, I could visit, etc. I tested other email websites, like, gmail or yahoo mail. I got the same error message. The problems could be duplicated in IE and Comodo Dragon. Most interesting, visiting non-email sites presented no problem at all for all three browsers.

Poked around using Google (as well as the Comodo forum) and could not find a suitable solution. Disable CIS Premium, no effect. Flushed the DNS, no effect, rebooted, no effect. I then slept on the problem and reasoned that the problem was common to three different browsers and was independent of CIS premium. Now, what else was common to the three browsers? Answer: the DNS settings on my computer.

In the morning, I checked the DNS setting (I knew they had been changed as part of the Comodo Dragon install a few months ago). The DNS settings were now and — both of these are Comodo settings … changed the second one to … the problem of just visiting the login pages for hotmail, gmail and yahoo mail still persisted. However, when I changed the DNS setting back to what I had before, that is, and and I could visit the login pages for and log into,, gmail and yahoo mail. The problem was resolved by not using the Comodo DNS Servers.

I hope that this solution can help others with similar problems.

Any explanation as to why the Comodo DNS servers would work in the morning but not 10 hours later (with the problem still persisting 12 hours later)?

AN ASIDE: This reminds me of a problem that I had about 5 or 6 years ago with Bell Canada and surfing. Some websites would just disappear and reappear within minutes. Even within a single browsing session of less than a minute, I could read a page and click on a link to another page on the same website and get an error message that the domain does not exist. Bell Tech support was no help. I eventually found the idea to change the DNS settings to and and my problems went away. I know nothing about inner workings of DNS servers … this is my experience with DNS. Solution: keep a listing of DNS servers and know how to change the DNS settings on your computer.

Its very frustrating for me. I found out until this morning, after many days having this problem, that COMODO DNS were not working properly.
At some time during the day, I cannot access gmail, facebook and other popular login websites.
So I changed my DNS to and now everything works fine.

Sadly, the DNS from COMODO are not that stable yet.

This problem was my dilemma as well for 2 days. Brighthouse techs helped me figure it out. It was the Comodo DNS that was blocking these sites. My neighbor and I both use Comodo and since the install of Comodo Dragon, we lost these pages as well as Facebook login. Solution for me was to go to Network places on my Vista PC and network connections on my XP laptop. Right click and choose properties. Then choose Internet Protocol Version 4 (TCP/IPv4). Now click on properties. At the bottom I chose: “Obtain DNS server address automatically”.
I have always been more comfortable with the Comodo DNS but because of this problem, the Brighthouse techs suggested the auto. This solved the problem and I ran over neighbors to do the same after my two PC’s. Hopefully we can get a message to let us go back to the Comodo DNS.
Hope this will help those who have similar problems.

Same here. Except that immediately when I was unable to visit Gmail and Yahoo etc, the message on my browser (CD) says the DNS lookup failed. So, I immediately changed my DNS (instead of waiting a few days!).