Thanks for your replies. Well I had such a problem with another game. Something about network balancing or network performance. After I unchecked this option my router worked again. So yes, a game can crash your router. How do I contact them? Looked at 'dayzmod.com' and couldn't find a way. When I get to the 'Contact the team' section it asks for login data. Which data do I have to enter? I bought the game via Steam and then downloaded the 'Six Updater'. I never gave them any login information. EDIT: Never mind found my way, lol, I'm blind or something, Its just right there. :D EDIT2: Found a thread with a similar problem: http://dayzmod.com/forum/index.php?/topic/39378-dayz-kills-whole-network/ maybe this solution works for some. Seems like it's not the fault of the character but of ArmA self. Friend just told me to test ArmA multiplayer and I had the same problem...