I noticed on steamforums people turning off Norton or Zone alarm because they cannot play the games with the firewall on. DONT I REPEAT DONT DO THIS!

1. always keep your firewall on.
2. always keep anti spyware on
3. always keep anti-virus software on.

if u cant play steam games with a Firewall running do this open up your firewall Allowed programs list or configuration and let the half life launcher allow steam and the game to access the internet change ur firewall settings to trusted zone this will allow communication to your game if your in the internet zone on ur firewall u may not be able to do soo..


Hope i helped .

ZoneAlarm makes EVERY game lag, I always turn it off for playing
(my Kaspersky keeps me safe, I guess )