Is it recommended to check this during installation of comodo? If it is, and I didn’t do this, how can I change it so that I can use comodo’s dns setting?
Hi,
It will try to prevent your system from accessing “known bad” ip addresses and this work like a sort of blocklist.
If you traffic is HTTP it will redirect you to a page telling you the destination is closed because of malicious behavior.
You can find instructions here on how to change this on a system:
Thanks for answering.
So is it sort of like subscribing to OpenDNS (see below), in which every time you try to open a web page it automatically filters and see if it’s bad, and if it is it will redirect to a closed page?
Yes
Unlike OpenDNS however, there is no user control over SecureDNS.
Thanks HeffeD then i hope that it falls under the “sort of” 
What exactly does it add “extra” ?
With OpenDNS, the user can filter by many different criteria. So in addition to the standard malware/phising blocks, you can also block by advertising, adult oriented, or even blogs if that is your desire. I think there are 50+ things you can filter by.
As well as whitelisting sites that you feel are mis-classified, or blacklisting sites you prefer all users on your network don’t visit.
I think in order for SecureDNS to be widely accepted, they need to work on something like this. I’m not sure if UltraDNS has this capability though, so it might not be possible.
I’m gathering that this DNS setting offered by Comodo is a safety feature to consider, but is it actually useful and good to use? Has anyone ever tried it?
There should be a discussion about it somewhere on the forum, use the search function to find it and jump in