I have Avira AntiVir Premium installed and when I tried to install Comodo firewall package it says I have Avira Security Suite installed, which is not right.
The same for me.
Avira Security Suite was never installed on this system.
I hope they are investigating this as I posted several times on the official announcement also.
Exaclty the same for me… I have Avira Antivir Personal…
So far only workaround I found is to install earlier version of CIS 4.0 and then do update through updater to 4.1. Firewall works without problems together Avira Antivir, but it is kinda lame to instal firewall this way.
1. Stop the Product protection
Protect files and registry entries from manipulation
http://i45.tinypic.com/65pevo.jpg
2.Open the registry
backup before delete it!
[HKEY_LOCAL_MACHINE\SOFTWARE\Avira]
delete Avira
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\Avira AntiVir Desktop]
delete Avira AntiVir Desktop
3.OK
Setup CIS4.1
and then
I forget to say that at last Import the backup reg files!
then start the Product protection! Dont forget it! 
Are you sure this is not going to crash Avira ?
Deleting HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\Avira AntiVir Desktop won’t crash Avira, but you will lose uninstall option for Avira in control panel. Not so sure about deleting Avira key in /Software part. Imo, backup that registry keys before deletion, install Comodo firewall and then restore key to registry , so you in theory won’t have troubles.
I forget to say that at last Import the backup reg files!
sorry!
It makes no sense to install cis and avira suite, one should only have a single resident software in each family, and adding softwares merely add bugs and lessens the global security.
If for whatever reason you do not want cis as an av (and i can understand that), the correct procedure is to install only cis firewall/defense+ and avira av.
No one here talks to install cis and avira security suite (av+firewall) together. Problem is that Comodo Firewall 4.1 standalone installer reports that Avira Security suite is installed on computer even if ONLY Avira ANTIVIRUS (both free and premium) is installed instead.
I install the CFW in the OS with Avira AntiVir Premium without Firewall, It’s also say the Incompatiblility with it, and recommend me to uninstall it. And about Kingsoft, Kingsoft has many produnt, no less than Antivirus! I think the check of Registry can’t define the Incompatiblility! It is not a good method, I think. Thanks!
I didn’t read thoroughly.
It seems it is now a fixed bug:
https://forums.comodo.com/install-setup-configuration-help-cis/conflict-between-comodo-firewall-and-avira-antivirus-t57133.0.html
todays date( 6-4-10 )
todays time ( 7:01am )
just so every one knows, the comodo installer(free version) is not fixed yet.
they have not fixed the bug yet in the free comodo installer yet.
i just downloaded it again today and its the same installer with the bug(glitch).
If anyone would bother to read entire posts, he/she would notice it says “will be available next week”…
ok, thanks