Not always recognizing DHCP requests?

I installed Comodo Firewall 3 a while ago to replace Kerio 2.1.5. But somehow I cannot get it to work properly. I have already installed it 3 times, after removing it using the advice on this forum. I have also removed every reference to Kerio I could find.
It seems Comodo is working as expected sometimes, but not always and consistently.
I’ll open separate topics for the different issues, to keep things clear…

Apparently Comodo does not see all DHCP requests.
I have the firewall security level set to custom policy mode. I have removed all rules from “application rules” and “global” rules, so Comodo should alert me about all network activity (right?). However, if I renew my IP address (“ipconfig /renew”), most of the time I don’t get any alert. Sometimes I do get an alert about svchost.exe sending a packet to UDP port 67, as expected…
Everything else seems to generate alerts as it should.

Your naking alot of posts. Why don’t you try leaving Comdo at default values. Works great for me. Firewall is set to “train with safe mode” and D+ is set at “clean PC Mode”. I ran the stealth port wizard and slected the option to “block all in coming connections”. Works fine. If you run the stealth port wizard first delete all your global rules.

Hi Ne,this has been reported you need to do an “ipconfig/release” first
Look at


It is rule based, so it should just do what the rules tell it to do, whatever those rules are. If I have a rule to block svchost.exe sending UDP packets out to port 67, Comodo should block that, right (given it is in “custom policy mode”)? It might not make sense to block DHCP, but it should respect the defined rules.

Probably something is wrong with my installation of Comodo, considering D+ is also acting weird. But that’s what I’d want to find out.

riggers, I think you made a mistake in your link, it links to this thread.

Try doing a complete uninstall and reinstall. I use Revo Uninstall in advanced mode… When Comodo says reboot, dont and delete all registry and program files it finds then reboot. use CCleaner registry cleaner then reboot. Install Comodo.

Sorry ne i meant,


If you get a DHCP request popup and allow it, but don’t click remember, CFP will still remember for the rest of the session. If you click remember it will actually make a rule for it. Not quite what I expected coming from Kerio either. :wink:

Thank you all for the advice.
I have reinstalled Comodo again, but still… Maybe I’m just expecting things Comodo doesn’t do by design.

About remembering actions per session: how long is a session? Is it until next reboot?
Is it possible to view which actions are currently remembered? Apparently not all allow-actions are remembered. I tested it by telnetting:

  • telnet somehost
  • alert: allowed without “remember” checked
  • telnet somehost
  • alert again

So Comodo does not seem to remember TCP.
Is it only UDP, or only DHCP?