Hello All,
Not sure if I’m posting to the right place but I’ll give it a shot, as I’m kind of out of ideas now.
I have the latest version of Comodo Personal Firewall (free version) and I absolutely love it and have been using it since I got to know this product. Never had any issue with it up until recently.
Me and my friend are trying to play a quite old game called Magic the Gathering via Hamachi in LAN.
Now the interesting thing is that we manage to see each other, and basically start a match, but seconds after one of us accepts the other’s “invite” in the game, the program gives an error saying the other player has “unregistered” (meaning cancelled the invitem which does not happen actually) and disconnects us.
Now we have done extensive testing and found that Comodo is somehow interrupting the connection after accepting the Invite, as with Comodo FW turned off, the game works flawlessly.
I have looked on this forums and saw some Global Rules that may be added to Comodo FW to allow communication through Hamachi, but none of this helped. 
Any help would be greatly appreciated as I really want to play this game, but really don’t want to replace this excellent firewall to be able to do so.
Thanks in advance,
Kizsde