i would like to know which firewall works best with avast free? i am running windows vista. And got windows defender, but i would like to use comodo firewall.
no need to quote yourself, that won’t make you get an answer quicker
Personally i like online armor as my preferred firewall or privatefirewall for second choice, i do not like anything from comodo. Having a windows 7 system im quite happy with the built in firewall though as it is much better than previous version’s.
A good set up for you would be avast, online armor, malwarebytes and disable defender because it’s rubbish.
Why do you say Windows Defender is rubbish ???
It provides an additional layer of security if set up correctly. 
- real-time protection for downloaded files and attachments plus programs that run on my system
- Ability to scan inside archive files plus USB flash drives
Defender has always been rubbish and it doesn’t do anything different that avast already does, and in the eight years that i did use, it has never detected anything, it’s just a waste of resources imo but it wont hurt if the op want’s to leave it on.
You’ve got MBAM PRO Kenny so you definatly dont need defender.
But back to the topic…
I don’t know which is best - a matter of preference, both technical and moral (a lot of people are not keen on comodo corporate behaviour). The comodo FW does work ok with avast though.