*IMPORTANT- Patching this game to play co-op will erase all your old save files.
please follow instructions below:
1. install game (best is RELOADED version);
2. crack game using "RELOADED crack" in "update1.rar" (open crack folder and copy all those files into the directory where you installed the game: example - C:/Program Filesx86/Dead Island, and replace files when it asks you.)
3. after that open "update1.rar" folder, and copy all the files from "dead Island_update1_so_coop.rar" to your installation folder where you cracked the game, replace all files it asks you to.
4. install steam from "steam" folder, let it update and create a new account (I would adivse you to use a fake steam account.)
5. open "smartsteam" folder from "update1.rar" and copy all files to: C:/Program Files (x86)/Steam and make a shortcut of smartsteam.exe on your desktop (you will only be using smart steam)
6. install tunngle, you can find it in "update1.rar" and create an account (if you don't allready have one) then restart your computer.
7. Apply update 2 by copying files over to your Dead Island installation directory and replacing everything it asks you to.
8. Apply uddate 3 by copying files over to your Dead Island installation directory and replacing everything it asks you to.
9. run smartsteam and go to games, add a nonsteam game, browse and find your deadisland.exe in installation folder, check the box and press "add selected program".
10. create desktop shortcut of deadisland.exe from your game directory and check in the compatibility tab RUN IT AS ADMINISTRATOR.
11. Launch smart steam, then start tunngle, search dead island in tunngle and join the same server with the friend you want to play with. Then start dead island from steam or desktop.
12. to be abble to play co-op mode, go to settings
in game and do this:
Game type : cooperative
Game visibility : LAN
Public Slots : (u can choose how many people can join u 1-3)
other 2 options are not imprortant
13. Now start a game, after you get your first quest and finish the game's intro you can play with a friend by pressing escape and then game lobby.
14. Profit
Note* I think you might be able to use tunngle to play with other people over the internet but I haven't tried it
Note* If you want to play without steam , dont install the updates, only crack the game.
Enjoy...