Internet connection dead when using Protect ARP Cache + Packet Checksuming

I just noticed my internet connection won’t establish at startup if i enable “Protect the ARP Cache” and “Do Packet Checksum Verification” at the same time. Using just “Protect the ARP Cache” works fine but when i enable packet checksuming too, connection just doesn’t work.
This doesn’t happen right away but only when i set these two options and restart my PC.
It’s reproducable each and every time.

I’m using VDSL (VDSL modem->switch->PC). OS is Vista Home Premium 32bit, Comodo FW is the latest version available (

Can anyone else reproduce this?

Sorry i couldn’t enter version number and bit into title but descriptio itself was so long i couldn’t do it…

Is there really no one with same issue? Or maybe try to reproduce it?

I also have protect ARP cache enbled and get no problems. If I enable “Do Packet Checksum Verification” I can still access the internet but it is a lot slower - odd it did not have this effect with version 2.4. Maybe it is something to do with Vista, I use XP Pro.

Did you add a new network for your router and then use the stealth ports wizard?


No, i’m using direct connection. I just restored my partition from scratch and i’ll see how it’ll work now.

No, it’s just not working. I’ve tried it on perfectly clean Vista installation and connection just won’t go up when enabling these two features together. Only ARP cache protection is fine (alone) but with checksuming, no go.