DHCP Not working when Avast Firewall is On

[REDACTED]

Help guys,

I'd like to know if there is a windows app/service that controls that function so that I can whitelist it in the firewall, before I decide to uninstall the whole thing.

Regards,
Vlad

[Eddy]

There is no need to disable the firewall or whitelist anything.
Perform a repair of avast and if that doesn't solve it a clean installation.

[REDACTED]

I did both and nothing, as long as the avast firewall is active no interface can get dhcp.
Program is updated to the latest version. Anything else I could do?

[Eddy]

Does it work without the proxy ?

[REDACTED]

What proxy? I still can't figure out how to enable this, I will uninstalling the network card drivers.

[libor_b]

Hello Vlad,

please go to Protection -> Firewall -> System Rules and check whether DHCP is Enabled. If it is, go then to Protection -> Firewall -> Packet Rules and check whether there is DHCP rule and is Enabled and "Action" is Allow.

Thank you
Libor

[REDACTED]

Hello Vlad,

please go to Protection -> Firewall -> System Rules and check whether DHCP is Enabled. If it is, go then to Protection -> Firewall -> Packet Rules and check whether there is DHCP rule and is Enabled and "Action" is Allow.

Thank you
Libor

The System rule has always been enabled, I had to make a packet rule DHCP > Allow > UDP > in/out > 67,68,546,547 >All Profiles. and still I get no DHCP, as soon as I turn off the firewall, It's Working again, the firewall log or recent activity show no blocked attempts at anything.

[Zep111]

Was this already solved as I have the same issue? Packet rules & system rules are as advised here (still default setting after new installation).

With firewall on and attempting to renew the lease, wireshark is showing no activity on udp.port == 67 && udp.port == 68 while still having an apipa address (source address showing as 0.0.0.0 in wireshark).
The firewall logs aren't showing any blocks on ports 67 or 68.

After turning firewall off and again trying to renew the lease the dhcp lease is renewed.

Once the PC has a non-apipa address dhcp renewal works correctly.