NIC doesn't get IP by DHCP while Comodo is open


i have a wireless lan router with DHCP. On connect I get an IP, but only if commodo is configured to allow all traffic. If it is configured normal, the WLAN card has an reduced connectivity (no IP) and so no internet is possible.

What can I do to solve this problem?

Thanks for help.

Has nobody an idea? I began to like Comodo Firewall, but if that problem is not solved, I go back to my old product.


make trusted connection via wizard in advanced to the router.

what did help me also is have disable “block outbound connections” while boot.

however it depends how you use comodo as trusted network or not.

if that fail might make a ruleset for dhcp, its 68 imho udp without trusted network.

you might read help how ways to use comodo.

make sure to limit to your subnet for dhcp rule.


Allow svchost.exe .
If you need specific rule,

Dhcp client Service Name: Dhcp Process Name: svchost.exe -k netsvcs Microsoft Service Description: Manages network configuration by registering and updating IP addresses and DNS names (This is how your computer gets a Dynamic IP address so you can connect to the internet. If Internet Connection Sharing is enabled, you need DHCP Client. Also required for most DSL/Cable connections.)

UDP Ports 67:68

Allow UDP Local port 68 Remote port 67

by Stem

tnx pedro,

might i add on, if use a trusted connection the mask is,

but i heard dhcp global runs at

you might need edit depending what config you use.

at least follow pedro, i just did post in case others might read.


Sure, tie the rule with the IP and mask of your router.

DHCP is one of the cases of “which comes first”? To send packets, there first needs to be an IP address, but DHCP is the means to get the address to be used.

DHCP uses two predefined addresses for a host that is trying to get a real valid address.

The host takes the sender address of (sometimes called the “me” address), and sends to the LAN local broadcast address of A DHCP server will listen for a query, and reply using the underlying Ethernet MAC addresses to tell the host its assigned IP address.

A DHCP rule will look like this:

allow out protocol IP from host to host
allow in&out protocol IP from LAN to LAN

The second rule is something of a catchall, as you may not know what the address is for your DHCP server. If it is your private LAN, then you know the IP address, but office environments have a bad habit of moving things around and not telling anybody.