Firewall Problems

Hi, I installed Comodo Internet Security, and now my network does not function with any router in front of my cable modem. If I remove the router and connect directly to the internet using just the cable modem, then my network is fine.

My ASUS motherboard has 2 Marvell Yukon 88E8056 PCI-E ethernet controllers onboard. In looking at the drivers shown in the Properties window for the Marvell controller, there is a new driver identified as the Comodo Firewall Driver.

If I uncheck the Comodo Firewall Driver, then my router and internet connection works fine. If I check the Comodo Firewall Driver, then the router is no longer visible; and the internet is no longer available.

Am I configuring this incorrectly, or is there a Comodo Firewall driver problem? Any help with this would be appreciated.


Do you have CIS set to automatically detect new networks? Your network changes when the router gets placed in between.

Does your modem/router setup work when CIS is not installed and Windows Firewall is active? Did you setup the router correctly with MAC address cloning (assuming that it is needed, it is in my country with hooking up cable modem on a router)?

Hi, it is set to automatically detect new networks, and it worked fine with Windows Firewall. My network connection died when I installed CIS.

Go to Firewall → Advanced → Network security policy → Applications → now look up System in the list and see how it is set. How is it set?

If it is set to block set it to outgoing only or browser.

Are CIS and Windows Firewall at the same time? If so disable Windows Firewall when CIS is active. What other security programs do you have running in the background?

Hi Eric,

Thanks for your help. System was set to custom with rules in place to allow traffic between my system and my dlink router. I first changed system to web browser and turned on the firewall. I could no longer see the internet. I then disabled the windows firewall and turned on the Comodo firewall driver.

Again, I could no longer see the internet. I now have the Comodo Firewall driver unchecked, windows firewall active and CIS running. With that configuration, I can see the internet.

I do not have any other security programs running. Hope this helps.

Do you think an uninstall and re-install of CIS might help the issue?

Thanks again.

Well as further detail to this saga, I uninstalled and re-installed CIS. I disabled windows firewall prior to the CIS installation.

Lo and behold! Same problem. I couldn’t connect to the internet. This time though, there was a message in the firewall section of CIS stating that there was a problem with the firewall installation. The mesage section had a diagnose and repair option, which I did.

I then rebooted my system, and now the internet connection through the router works with the Comodo firewall drivers installed. Sounds like there was some kind of firewall installation issue in my first install that did not get flagged. However, it did get flagged on the second install. Go figure…

Glad you found the solution after some sort of weirdo trip…