Oct 4, 2012
L4D Blog
With today’s update and Steam’s Beta update we should have all of the “error 55” issues resolved. If you are in the Steam Beta program, make sure to accept the update to the beta today as that was causing a conflict.

When we had the issue with "Remove plug-ins” many players added “-insecure” to their command line. After we resolved the issue, if you still had “-insecure” in your command line it would continue to give you the "Remove plug-ins” error. We have updated this error text to give you the correct information. If you get an error that you are trying to connect to a secure server in an insecure manner remove –insecure from your command line launch options.

You can view the complete release notes here.
L4D Blog

The Steam Workshop website will allow you to browse, rate, and discuss thousands of community created add-ons and even install them directly to your game with just one click of the mouse. We are also going to try an experiment with the L4D2 Workshop that will allow content to appear in the L4D2 world even more seamlessly based on the community’s response.

L4D Blog

Left 4 Dead is going on a road trip this summer. If you missed the announcement, some of our common zombies made their way over to Counter-Strike: Global Offensive for the Zombie Mod.
L4D Blog

Today, Team Fortress 2 is adding co-op and robots to their game! There is only one problem - don’t worry, robots are just the zombies of the future that’s not the problem – the problem is this is 6 player co-op not 4. So you’re gonna need to find a few new friends, a younger brother, your mom, someone, anyone to join you and your three friend to fight the lethal horde of robots.

L4D Blog

Gib Fest
Blast the infected to shreds with M60s.

Swords can slice up some fun. Chainsaws can tear apart the infected. But you need to get close for both and well… chainsaws are really loud! Time to go with the ultimate gun, you and three friends armed with M60s and unlimited ammo. This is going to get messy.

Cold Stream is out for the Xbox 360!
For Xbox 360 players this is your first chance to play the 5 Campaigns contained in Cold Stream... We have all the details available on our Cold Stream update page at www.l4d.com/coldstream. Also With this update, you can now play any mutation at any time - just press the Y Button to cycle through to your favorites! (You need to own The Passing DLC for access to Mutations.)
Jul 24, 2012
L4D Blog

Cold Stream Is Out!
For PC players, we have some map updates that move the big Beta needle to Release. For Xbox 360 players sorry but the Cold Stream DLC on the Xbox 360 is going to be delayed until next week.

We have almost all the details available here on our Cold Stream Update page – we just missed one – to celebrate the launch of Cold Stream – Left 4 Dead 2 is 75% off on Steam! Time to introduce some new friends to the Zombie Apocalypse.

Visit the Cold Stream Update page.
Jul 13, 2012
L4D Blog
It has been too long since we had some stats, so we took a break today to run some numbers from yesterday’s (July 12th) activity on the PC.
237,412 Players played 7,147,979 minutes for an average session time of 30 minutes.
L4D Blog
Jun 29, 2012
L4D Blog
L4D Blog

Nightmare
You’ll never see them coming

This Survival Mutation was inspired by Karma Jockey. There are commons, plenty of beefed up Specials, no glows, and lots and lots of fog. If you like to be scared by things that jump out at you from the night, this one is for you.

What do Zombies Think?
While cleaning/moving our offices around (all our desks at Valve are on wheels so we can have desk races), we discovered this old, long ago used Zombie decision making tree. It was created before our session with Mike Patton to record the common zombie sounds. While it is near indecipherable gibberish thanks to bad penmanship, it shows not at an AI level how a zombie behaves but all the speech opportunities and transitions.

Our favorite is the top. Lay Down? Nope. Want to vomit? Sure.


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