How to play L4D2 split-screen on PC

Have you ever wanted to play L4D2 split-screen 2 players on 1 PC? if you did this guide will help you to do so.

Introduction

Have you ever wanted to play Left 4 Dead 2 split-screen with 2 players on 1 PC? you might think it's impossible but the split-screen mode is actually integrated into the game but it's just hidden.
You will need to access the developer console and execute some commands to achieve split-screen mode on your PC.
You can also pair 2 or more PC's on the same network and have more than 2 players.
This works for all game modes including mutations and even add-on maps.
I know lots of people struggle to do this and play flawlessly so if this guide helped you please let me know in the comments, and if you had any problems or didn't know what to do let me know in the comments too :)

The easy way

Let's begin with the easy way.
This method should work just fine if you have 2 Xbox 360 controllers (or any other x-input compatible controllers) hooked up to your computer, and it will allow you to play all of the game modes excluding mutations.
What you have to do is simply subscribe to this add-on .
Once you are subscribed and the add-on finished downloading, just launch the game (if it's not already) and the first thing you will notice is the addition of a new mode in the menu called split-screen.
to start playing simply click on the mode picture then choose what game mode you want to play split-screen then choose the map and other settings.
You can also change whether to split the screen vertically or horizontally by clicking on SS mode.
Once you're in-game you just start playing using the 2 controllers you have.
However, if you only have 1 controller, wanna play an add-on map. wanna play a mutation or even want to play LAN/online head over the next 2 sections.

The not-so-easy way

If the previous method didn't work for you for whatever reason, or let's say you have 1 controller, or maybe you wanna play a mutation or an add-on map then the second method should totally work for you.

If you have one controller

If you only have one controller to play with and you want the other player to use the keyboard/mouse you will need enable developer console.
To do so go to option> keyboard > then check "enable developer console", once you do so you can press the tilde key [wiki.unvanquished.net] to activate the console.
But, first things first, open a notepad from the start menu then copy and paste this code into it

name2 Player(2)
ss_splitmode 2
//ss_enable 1
joystick 1
joy_advanced "1" // use advanced joystick options (allows for multiple axes)

joy_name "L4D Xbox360 Joystick Configuration"
joy_inverty2 0
joy_advaxisx 3 // x-axis controls GAME_AXIS_SIDE (strafing left and right)
joy_advaxisy 1 // y-axis controls GAME_AXIS_FORWARD (move forward and back)
joy_advaxisz 0 // z-axis is treated like a button
joy_advaxisr 2 // r-axis controls GAME_AXIS_PITCH (look up and down)
joy_advaxisu 4 // u-axis controls GAME_AXIS_YAW (look left and right)
joy_advaxisv 0 // v-axis is unused
joy_forwardsensitivity -1.0 // movement sensitivity
joy_sidesensitivity 1.0
joy_forwardthreshold 0.1 // movement dead zone settings
joy_sidethreshold 0.1
joy_pitchsensitivity 1.0 // look sensitivity
joy_yawsensitivity -1.5
joy_pitchthreshold 0.1 // look dead zone settings
joy_yawthreshold 0.0

joy_variable_frametime 1
joy_autoaimdampenrange 0.85
joy_autoaimdampen 0.5
joy_lowend 0.65
joy_lowmap 0.15
joy_accelscale 3.0
joy_accelmax 4.0
joy_response_move 5
joy_response_look 1
joy_autoaimdampen 0.3
joy_autoaimdampenrange 0.85
joyadvancedupdate // advanced joystick update allows for analog control of move and look

// Alternate control 1
cmd1 bind "0" "slot10"
cmd1 bind "1" "slot1"
cmd1 bind "2" "slot2"
cmd1 bind "3" "slot3"
cmd1 bind "4" "slot4"
cmd1 bind "5" "slot5"
cmd1 bind "6" "slot6"
cmd1 bind "7" "slot7"
cmd1 bind "8" "slot8"
cmd1 bind "9" "slot9"
cmd1 bind "a" "+moveleft"
cmd1 bind "c" "+voicerecord"
cmd1 bind "d" "+moveright"
cmd1 bind "e" "+use"
cmd1 bind "f" "impulse 100"
cmd1 bind "h" "motd"
cmd1 bind "m" "chooseteam"
cmd1 bind "q" "lastinv"
cmd1 bind "r" "+reload"
cmd1 bind "s" "+back"
cmd1 bind "t" "impulse 201"
cmd1 bind "u" "messagemode2"
cmd1 bind "w" "+forward"
cmd1 bind "x" "+mouse_menu QA"
cmd1 bind "y" "messagemode"
cmd1 bind "z" "+mouse_menu Orders"
cmd1 bind "`" "toggleconsole"
cmd1 bind "SPACE" "+jump"
cmd1 bind "TAB" "+showscores"
cmd1 bind "ESCAPE" "cancelselect"
cmd1 bind "SHIFT" "+speed"
cmd1 bind "CTRL" "+duck"
cmd1 bind "F1" "Vote Yes"
cmd1 bind "F2" "Vote No"
cmd1 bind "F5" "jpeg"
cmd1 bind "MOUSE1" "+attack"
cmd1 bind "MOUSE2" "+attack2"
cmd1 bind "MOUSE3" "+zoom"
cmd1 bind "MWHEELUP" "invprev"
cmd1 bind "MWHEELDOWN" "invnext"


// controller2 bindings
cmd2 +jlook // enable joystick look
cmd2 bind "A_BUTTON" "+jump;+menuAccept" // (A) button - Jump -menuAccpt allows us to make selections on hud menus
cmd2 bind "B_BUTTON" "+reload" // (B) button - Reload
cmd2 bind "X_BUTTON" "+use" // (X) Use
cmd2 bind "Y_BUTTON" "lastinv" // (Y) button - swap pistol/rifle or z_abort -used to respawn as a ghost.
cmd2 bind "R_TRIGGER" "+attack" // RT - Main weapon - Primary trigger
cmd2 bind "L_TRIGGER" "+attack2" // LT - Melee
cmd2 bind "R_SHOULDER" "+lookspin" // RB - Fast 180 spin
cmd2 bind "L_SHOULDER" "toggle_duck" // LB - Duck - is also used to give objects to people.
cmd2 bind "STICK1" "vocalize smartlook" // LS - vocalize
cmd2 bind "STICK2" "+zoom" // RS click - Rifle Zoom

// Fixed bindings, do not change these across joystick presets
cmd2 bind "BACK" "togglescores" // (back) button - scores
cmd2 bind "START" "pause" // (start) button - pause
cmd2 bind "S1_UP" "+menuUp" // Hud menu Up
cmd2 bind "S1_DOWN" "+menuDown" // Hud menu Down
cmd2 bind "UP" "impulse 100" // DPad Up - Toggle flashlight
cmd2 bind "LEFT" "slot3" // DPad Left - grenade
cmd2 bind "RIGHT" "slot4" // DPad Right - health
cmd2 bind "DOWN" "slot5" // DPad Down - Pills
sv_cheats 1
in_forceuser 1	

Save the notepad file with any name you want (i chose split-screen.txt) into:
Steam > steamapps > common > Left 4 Dead 2 > left4dead2 > cfg

Once you do that head over to your game and open developer console and type in:

 exec split-screen.txt	

NOTE: In my case, the name was split-screen.txt, depending on the name you chose you would exec the name of your txt file.

Then simply launch a split-screen session using the add-on from the previous section, you will be able to play with 1 controller and one keyboard/mouse combo.

If you want to play an add-on map

Unfortunately the previous add-on doesn't support launching add-on maps that aren't in the official list, to do so you will need the help of our friend Mr. developer console.

First you will need to know the name of the map you want to play, to do this simply launch a single-player game from the main menu with the add-on map you want to play, while in-game pause and then launch the developer console, in the top right corner there should be some text (You can move the console window away if it's blocking the text), the second line should say the exact name of the map right after "Map" and between the quotation marks, in this case it was the first chapter of Dead Center.


Just write the name down and you can quit the single-player session.

On the main menu launch the developer console and type in the following command

 map "mapname"	

Replacing "mapname" with the name of the add-on map you wrote down before, it would be something like this in our previous case:

 map c1m1_hotel	

Once you're in the game you will need to launch the split-screen session, to do so open the console again and simply type in:

 connect_splitscreen localhost 2	

Your game should re-load and you will be playing split-screen on your add-on map

If you're using 1 controller and keyboard/mouse you can also run the split-screen.txt script after executing the map.

NOTE: You can use this method for official maps if the split-screen add-on didn't work for you or you can't download it for some reason.

If you want to play mutations (or any game mode on add-on maps)

When you launch a map using the command

 map "mapname"	

It'll usually start the game in campaign mode, however if you want to play a game mode other than that you will need to type in the game mode name after the map name just like the following:

 map "mapname" "mode"	

An example of this if you want to play Versus on Dead Center's first chapter

 map c1m1_hotel versus	

Mutations work the same way but their names can be a bit tricky to find, you can click here [forums.alliedmods.net] to check out some names for a couple of mutations.

Once again, if you're using 1 controller and keyboard/mouse you can also run the split-screen.txt script after executing the map with your desired game mode.

 connect_splitscreen localhost 2	

You should now be playing in the game mode you want on any map you want, If you are playing with one controller and one keyboard/mouse use the trick in the beginning of this section.

Playing in LAN or Online

You should now be able to play Left 4 Dead 2 in split-screen with another friend on 1 PC, and the game doesn't support more than 2 players on one machine, so what to do if you want to have more players?

If you want to play the game with 3, 4, or even more players you will need more than one PC, all of them connected to the same network, and L4D2 is installed on all machines. But, still how do you do it?

Let's take an example first, we are 4 players with 2 PC and we want to play together whether it's co-op campaign or versus.

Make sure all PC's are connected to the same network (wired connections result in less latency), one of the computers will host the game with 2 players and the other will join in with 2 players so you will have a total of 4 players.

To host a game, pick one of the computer to be the host, you will get better results if this computer is the one with better hardware and better connection to your router, it wouldn't make much difference but can sometimes result in a better experience.
On this computer navigate to
Steam > steamapps > common > Left 4 Dead 2
Right click on left4dead2.exe and click "create shortcut", this should place a shortcut in the same folder, right click on that shortcut and click properties, in the target section it should say the path to the exe file we just mentioned, just move to the end and add a space then "-insecure" like in the following example.

 "D:\Steam\steamapps\common\Left 4 Dead 2\left4dead2.exe" -insecure	

(WITH the quotation marks)
Click OK.
Launch the game from the shortcut, open the developer console and input these 2 commands

sv_lan 1
sv_allow_lobby_connect_only 0	

Then just follow the previous section to start a split-screen game with the map and game mode you want. pause the game and launch developer console, type in the following command

 status	

You should get some text in the console interface, look for "udp/ip" line, in front of it you will find the IP address of the server it will look like

 192.168.1.100:27015	

Write down this bit, now we shall head over to the other computer that should join our game.


Do the same shortcut trick mentioned above on this computer as well, start the game and launch developer console and input the following command

 connect_splitscreen "ipaddress" 2	

Replace "ipaddress" with the IP address we got from the status command on the host computer and it will look something like this.

 connect_splitscreen 192.168.1.100:27015 2	

This should connect you to the host computer with 2 players and you will have a total of 4 players on the same server.
If any of the computers has players using keyboard/mouse plus controller combo refer to the previous section to make it playable with 1 controller and one keyboard/mouse by executing the split-screen.txt script.

If you want to play as 3 players you will want the client computer to join in as a single-screen player, to do so input the following command:

 connect "ipaddress"	

In the previous case it would be:

 connect 192.168.1.100:27015	

(Without the splitscreen part)

If you wanna do this Online, it will be the exact same steps except that the host computer must have his router port forwarded for steam ports, if you don't know how to port forward your router, just search on Google " How to port forward "router name" ", Since this process differs for each router you will have to do it on your own.

Conclusion

This pretty much wraps it up on how to play Left 4 Dead 2 split-screen.
If this guide helped you please let me know in the comment section,rate and also favorite.
And if you had any problems report them on the comments please.
Thank you for your time and have fun!

Extra notes (may be updated)

By: Trevolon

If player 2's camera doesn't move up and down, input the following command into console or add it to the txt file:

cmd2 +jlook

By: Fens

To choose the survivors you want, do either of the following commands:

cmd1 sb_takecontrol survivorname

for player 1, and:

cmd2 sb_takecontrol survivorname

for player 2.

By: Florantin

Incase you get weird interaction between your controller and keyboard, as in pressing controller buttons or keyboard keys switches up which controls which, open steam overlay (shift+tab) while in-game with the controller connected, go to controller options and uncheck "use configurations for non-steam controllers".

By: Daddy Friddle

For those having trouble, confused
He should have said split-screen.cfg I made mine splitscreencstm.cfg because there already was a splitscreen-on and -off file there I didn't want to get confused with.

Random notes 8/2021

Hey guys, I'm sorry it's really hard to manage all these issues together, I just tried it again and it worked. So here's a few things to check for:
1- When using one controller and KB/M (keyboard/mouse) the KB/M player MUST be player 2, as there is no way (that i know of) to move the one controller into the second slot, but the KB/M can be forced to control player 2.
2- Make sure all of your controllers are plugged in before launching the game.
3- This script is mainly for Xinput controllers (xbox360 and xboxone controllers) and anything that emulates them. If you have a PS4 controller you need to use DS4Windows[ds4windows.com] (with exclusive mode or with using the program HidHide[github.com]), or using SCPToolkit[github.com] for PS3 controllers, or XOutput[github.com] if you have a generic USB joystick.
4- Try disabling steam input auto configuration thingy, I don't know exactly how to but check around in Settings>Controllers or from within the in-game overlay.
5- For the people getting "couldn't exec" I really have no idea what causes this. The only thing i can tell you is to make sure you placed your txt file in the folder "Left 4 Dead 2/left4dead2/cfg/". Also try running the game or steam in admin mode, or maybe move your game installation to somewhere else, sometimes folder names can cause issues (very long names or foreign characters).
6- As far as I know you can't connect to official servers in splitscreen, but you can connect to dedicated/private servers if you have their IPs (check the LAN/online section).
7- (just checked this) From the splitscreen add-on page, there seems to be a solution to assign the controller to player 2 using a program called "Joystick and HOTAS port mapping program - JoyID"[theairtacticalassaultgroup.com], I haven't tested this and I have zero clue on how to use it though.
8- For the people who get their keyboard switched when firing, try this fix:

Publicado originalmente por Eslovaco Beijæmin À Rolan|:

Got it to work by using the SFKTeam's custom menu mod, disabling "Input Per-Game Setting > Forced Off [Thanks, «Moghart»]" and modifying the "FrangoRobô/RobotChicken" config to make the controller control the first player. The config ended up like this: https://pastebin.com/beNeXEyf

9- If all else fails, or you want more than 2 players on the same PC, or you want split monitors, consider checking out Nucleus Coop[github.com], they have a script for L4D2 where it launches more than one instance of the game assigning different controlling devices (KB/M and/or controllers) to different instances and positions the windows so it looks like it's regular splitscreen. It might be a bit unstable and it requires a much stronger PC but it's a solution that might be useful for some people.

[Pepito]

error COUDNT EXEC SPLITSCREEN ARCHIVO

[Sweetheart]

so where do i put setinfo mate?

[ingspoveda]

There is a little error on the code to copy and paste... At the beggining the command "setinfo" is missing, and that causes that all the code can not be executed.

[TRDL]

Both the controller and Mouse&Keyboard keep controlling the same person.

[Star Reshiram]

@(playing on Neuralink 5G) Did it still give you the error message in console when you changed it? It does for me.

[idiot 3 alt (7)]

https://youtu.be/DdmNYNkcwKE

[Pingus]

DON'T PUT IT IN THE CONSOLE COMMANDS IT BRICKED MY WHOLE GAME. I need a fix asap, how can i reset the game to it's original state

["The Hilarious" Ross Matthews]

Hey mate I just noticed I was getting an error
Unknown command "joy_variable_frametime"

Once I changed it to 'timeframe' in the cfg file it worked like a dream! Thanks for posting this

[MilkyWay]

Does this work for connecting to a dedicated server? nothing happens when i submit the command.

[oswald berillium]

how many people can play the split screen is it just 2?