Current Game Version: v2.0.1.8 [may 21] THE PASSING DLC is now available andThe first post-DLC Update is here!!
Authoring Tools and Add-on Support updates!Updated guide structure as per request.
Game Details:

Set in the zombie apocalypse, Left 4 Dead 2 (L4D2) is the highly anticipated sequel to the award-winning Left 4 Dead, the #1 co-op game of 2008.

This co-operative action horror FPS takes you and your friends through the cities, swamps and cemeteries of the Deep South, from Savannah to New Orleans across five expansive campaigns.
You'll play as one of four new survivors armed with a wide and devastating array of classic and upgraded weapons. In addition to firearms, you'll also get a chance to take out some aggression on infected with a variety of carnage-creating melee weapons, from chainsaws to axes and even the deadly frying pan.

You'll be putting these weapons to the test against (or playing as in Versus) three horrific and formidable new Special Infected. You'll also encounter five new “uncommon” common infected, including the terrifying Mudmen.

Helping to take L4D's frantic, action-packed gameplay to the next level is AI Director 2.0. This improved Director has the ability to procedurally change the weather you'll fight through and the pathways you'll take, in addition to tailoring the enemy population, effects, and sounds to match your performance. L4D2 promises a satisfying and uniquely challenging experience every time the game is played, custom-fitted to your style of play.

Here's how to play without Steam mucking everything up, and how to update without the need for Steam:












NOTE: This is for informational and educational purposes ONLY!
It provides an alternative means to updating and playing without Steam.
Please support your favorite game developers!

Prerequisites:

Microsoft Visual C++ 2008 SP1 - Download and install: 32-bit or 64-bit

Microsoft's .net Framework 3.5 - Download and install .net 3.5

Quick Setup:

I. Install Left 4 Dead 2

II. Update Left 4 Dead 2

III. Install Add-on Support

IV. Patch Game with Rev-Emu

V. Play by executing Left4Dead2.exe

VI. [Optional] Install L4D2 Authoring Tools

Detailed Information:

I. Install Left 4 Dead 2:

Download and Install Left for Dead 2.
From Steam, Razor's release or, better yet, grab the clean 2.0.0.0 files linked below..

II. Update Left 4 Dead 2:

Update L4D2 to the latest version using the update installers linked below:
The Full Update will update any version of L4D2 and includes client and server files and a backup of original CEG protected client.dll included- use this one first if you're not sure.
Incremental Updates will update only one specific version to another specific version - use these to bring L4D2 up to the latest version.
After, and only after, installing latest update: Patch the game with Rev_emu.

III. Install Add-on Support:

Add-on Support Package will allow you to run any custom map,
including the ones released for original L4D.
1- Install the Add-on Support package
2- and then install the latest Add-on Support Update to bring you up-to-date.
3- To fully utilize Add-on Support see L4D1 on L4D2, Custom Campaigns and Maps.

IV. Patch Game with Rev-Emu:

1- Install Latest Rev-Emu Installer which includes left4dead2.exe and Setti masterserver.vdf.
Install to your Left 4 Dead 2 Installation Folder and choose which fix to use [either RevEmu or RevExe:].
2- Edit rev.ini with notepad to change your name. [SteamUser=YourName and PlayerName=YourName]
3- Edit rev.ini depending on how you would like to play:

• For playing single player via the main menu:

Edit rev.ini with notepad and comment out the ClientDLL line with a # like this:
#ClientDLL=steamclient_l4d2.dll

• For playing online and enable serverbrowser and SteamGroupServer on main menu:

Edit rev.ini with notepad and confirm the ClientDLL line is not commented out:
ClientDLL=steamclient_l4d2.dll
Go into your Left 4 Dead\bin\config folder and make sure Masterserver.vdf is set to Read-Only.
[The latest RevEmu installer will set this to read-only for you]
NOTES: Use openserverbrowser in console to open the server browser.
Setti servers will now show up in the custom tab of the server browser.
Favorites tab doesn't work - Don't use it - it will crash your game
SETTI Steam Group Servers will be available via the Main Menu for quick connection to servers!!

V. Play by executing Left4Dead2.exe:

Create a shortcut on your desktop to left4dead2.exe and add -console -novid -nohltv to its launch parameters:
Right click your shortcut, select properties. In the "Target" field, you should have:

"C:\Program Files (x86)\Left 4 Dead 2\left4dead2.exe" -console -novid -nohltv

[The latest Rev-Emu installer will create a desktop icon for you.]
For more information on console commands, startup parameters and to further customize your gaming experience read Left 4 Dead 2 - Making a Custom AutoExec.cfg.
Play Left 4 Dead!

VI. [Optional] Install L4D2 Authoring Tools:

Install the Authoring Tools package into your L4D2 installation folder, and then make a shortcut to SDKLauncher.exe [located in yer \bin folder].
Get Started with Valve's L4D Authoring Tools Wiki.
ganesh007 wrote up a great L4D2 SDK Tutorial which I highly recommend!!

If you previously used Stryder Loader and wish to move to the New Rev-Emu:

1-Remove Stryder Loader:
delete stryder.dll, stryder.ini, stryder.txt, IniGen.exe from root folder and remove Name Enabler Addon.
2-Install repacked update with new patched client.dll.
3-Install latest rev-emu.


THE PASSING DLC is now available!!

:DOWNLOADS:

1- Download and Install Current Full AND Incremental Update:

Full Update from any version to 2.0.1.3
Includes "The Passing" DLC.
[Now 100% compatible with razor release - no need for razor update]
[715 MB exe \ 1.24 GB installed]
L4D2_Full_Update_2013_The_Passing.exe
MEGAUPLOAD

Latest Incremental Updates:
[Post-DLC Updates]

*NEW* Update from 2.0.1.3 to 2.0.1.8-2 *NEW*

[84.1 MB exe \ 230 MB installed] -update 5-21-2010
L4D2_Update_2013_to_2018.2.exe
MediaFire

2- Download and Install Addon-Support Tool:

*NEW* L4D2 Full Add-on Support *NEW*

[install to allow running any custom maps]
[includes jan12 & feb 5 add-on support updates]
311 MB exe / 817MB installed
MegaUpload

3- Download and Install Current RevEmu:

*NEW* L4D2_Rev_Emu_for_v2018 *NEW*
[for L4D2 v2018]
MediaFire

4- [OPTIONAL] Download and Install Authoring Tools:

L4D2_Authoring_Tools_April23
Repacked - Now includes an uninstaller.
[Full and Updated Authoring Tools Package]
19.3 MB exe \ 81.4 MB installed
MediaFire



For those who have been following along and are at v2018:

*NEW* Update from 2.0.1.8 to 2.0.1.8-2 *NEW*

[1.26 MB exe \ 2.64 MB installed] update 5-21-2010
L4D2_Update_2018_to_2018.2.exe
MediaFire

----------------- OLD UPDATES/MISC FILES -----------------
These are OLD and OUT-DATED Files- For Archival Purposes Only
For advanced use: Only use if you know what you are doing.

left 4 dead 2 v2.0.0.0
CLEAN files in 6 parts:

[4.06 GB total parts\ 6.15 GB installed]
Download from MegaUpload
If you experience any issues, try the following steps to make sure your download is not corrupt:
Put all six parts into the same folder and Extract l4d2_v2000_Clean.zip_TestFiles.zip with them.
Run Testfiles.exe to make sure all parts are OK.
If you receive an error, a part may be corrupt - Download the corrupt file again and re-test.
When all parts pass the checksum test, Open .001 using 7zip.
Then extract the entire contents of the archive to Program Files/left 4 dead 2.

-----------------
Update from 2.0.1.3 to 2.0.1.8[83.9 MB exe \ 230 MB installed] -repacked 5-17-2010
L4D2_Update_2013_to_2018.exe
MediaFire

Update from 2.0.1.7 to 2.0.1.8

[8.75 MB exe \ 28.3 MB installed] -repacked 5-17-2010
L4D2_Update_2017_to_2018.exe
MediaFire

L4D2_Rev_Emu_for_v2017
[for L4D2 v2017 and higher]
MediaFire

Update from 2.0.1.3 to 2.0.1.7[83.8 MB exe \ 229 MB installed]
L4D2_Update_2013_to_2017.exe
MediaFire

Update from 2.0.1.6 to 2.0.1.7

[8.73 MB exe \ 28.1 MB installed]
L4D2_Update_2016_to_2017.exe
MediaFire

Update from 2.0.1.3 to 2.0.1.4

[102 MB exe \ 221 MB installed]
L4D2_Update_2013_to_2014.exe
MediaFire

Update from 2.0.1.4 to 2.0.1.5

[2 MB exe \ 7.8 MB installed]
L4D2_Update_2014_to_2015.exe
MediaFire - RapidShare

Update from 2.0.1.5 to 2.0.1.6

[2.9 MB exe \ 10.7 MB installed]
L4D2_Update_2015_to_2016.exe
MediaFire - RapidShare

L4D2 Add-on Support

[install to allow running any custom maps]
308 MB exe / 811MB installed
Download: MegaUpload
Alternate Link <-thanks whoever posted it in the comments.

L4D2 Add-on Support Update Feb5
[includes jan12 & feb 5 add-on support updates]
97.5 MB exe \ 206 MB instaled
RapidShare - MediaFire

L4D2_Rev_Emu_for_v2014
[for L4D2 v2014 and higher]
MediaFire


Incremental Updates:
[For those who have been keeping up.]

Update from 2.0.1.1 to 2.0.1.3
Includes "The Passing DLC"

[688 MB exe \ 1.05 GB installed]
L4D2_Update_2011_to_2013.exe
MegaUpload

Update from 2.0.1.0 to 2.0.1.1
[10.9 MB exe \ 24.8 MB installed]
L4D2_Update_2010-2011.exe
RapidShare - MediaFire

Update from 2.0.0.9 to 2.0.1.0
[10.9 MB exe \ 41.7 MB installed]
L4D2_Update_2009-2010.exe
RapidShare - MediaFire

Update from 2.0.0.8 to 2.0.0.9
[6.41 MB exe \ 30.6 MB installed]
L4D2_Update_2008-2009.exe
RapidShare - MediaFire

Update from 2.0.0.7 to 2.0.0.8
[12.9 MB exe \ 63.9 MB installed]
L4D2_Update_2007-2008.exe
RapidShare - MediaFire

Update from 2.0.0.6 to 2.0.0.7[repacked]
[5 MB exe \ 19.3 MB installed]
L4D2_Update_2006-2007.exe
RapidShare - MediaFire

Update from 2.0.0.5 to 2.0.0.6
[2 MB exe \ 7 MB installed]
L4D2_Update_2005-2006.exe
RapidShare - MediaFire

Update from 2.0.0.4 to 2.0.0.5
[3 MB exe \ 12 MB installed]
L4D2_Update_2004-2005.exe
RapidShare - MediaFire

Update from 2.0.0.3 to 2.0.0.4 -repack
[12.5 MB exe \ 59.7 MB installed]
L4D2_Update_2003-2004.exe
RapidShare - MediaFire

Update from 2.0.0.2 to 2.0.0.3
[4 MB exe \ 14.3 MB installed]
L4D2_Update_2002-2003
RapidShare - MediaFire

Update from 2.0.0.1 to 2.0.0.2
[5.38 MB exe / 18.7 MB installed]
L4D2_Update_2001-2002.exe
Download from RapidShare - MediaFire

Update from 2.0.0.0 to 2.0.0.1
[7 MB \ 32.4 MB installed]
L4D2_Update_2.0.0.0_to_2.0.0.1.exe
Download from RapidShare - MediaFire

L4D2_Rev_Emu_Fix_v2011
Working SP, MP and Steam Group for v2011 [creds to KKHafi].
[includes cracked left4dead2.exe and Setti masterserver.vdf]
Install to your Left 4 Dead 2 Installation Folder.
Set Left 4 Dead 2\bin\config\Materserver.vdf to Read-Only!
Edit rev.ini with notepad to change your name.
Backup of Original v2011 files included in bin folderMediaFire

L4D2_Rev_Emuv9.81R4-Fixed2 [creds to KKHafi]
Working SP, MP and Steam Group for v2011.
The L4D2 RevEmu v9.81R4-Fixed2 includes:
Revolution Emulator v9.81R4, Setti Master Servers,
previous DLL and backup of current DLL.
To install: select rev-emu, un-check backup, and install to L4D2 directory.
MediaFire

L4D2_Rev_Emulator_v2010 [v9.81R4]
For version 2.0.1.0 and higher.
[includes cracked left4dead.exe, Setti masterserver.vdf and
Original v2010 dll's renamed with "_l4d2"]
Install to your Left 4 Dead 2 Installation Folder.
Set Left 4 Dead 2\bin\config\Materserver.vdf to Read-Only!
Edit rev.ini with notepad to change your name.
RapidShare - MediaFire
NOTE: Singleplayer doesn't work - Use for multiplayer only
see alternative loader for singleplayer action

L4D2_Rev_Emulator [v9.81R4]
For version 2.0.0.9 and earlier.
[includes cracked left4dead.exe and Setti masterserver.vdf]
RapidShare - MediaFire

L4D2_Authoring_Tools_feb20
[Full and Updated Authoring Tools Package]
19.1 MB exe \ 81.9 MB installed
RapidShare - MediaFire

Full Update to 2.0.1.1
[40.9 MB exe \ 248 MB installed]
L4D2_Full_Update_to_2.0.1.1.exe
RapidShare - MediaFire

Full Update to 2.0.1.0

[40.9 MB exe \ 248 MB installed]
L4D2_Full_Update_to_2.0.1.0.exe
RapidShare - MediaFire

Full Update to 2.0.0.9

[38.2 MB exe \ 243 MB installed]
L4D2_Full_Update_to_2.0.0.8.exe
RapidShare - MediaFire

MORE INFO / FURTHER READING

--------------------------------------About Setti MasterServer.vdf--------------------------------------

For ServerBrowser Support of Private Servers.

Direct Link

Add Setti as the MasterServer: [Now included with Rev_Emu_Installer]

1. Download MasterServers.vdf from here: http://css.setti.info/code/masterserver/
2. Create a folder named 'config' inside the 'bin' folder. [Ex. C:\Program Files\Left 4 Dead\bin\config]
3. Copy MasterServers.vdf to the config folder, right click and set its attribute to read-only.
4- Go to your L4D shortcut [used to launch game]. Right click it and select properties.
5- In the shortcut tab, add -console -serverbrowser to the end of the target line. Click Apply and OK.
6- Open the game, go into console and type: openserverbrowser.

-----------------------------------------Alternative Playing Methods----------------------------------------

In the method above, a pre-patched client.dll is included by default with the full and incremental updates. The pre-patched client is made to work with the above Rev-Emu. Backup [.bak] of the untouched dll is included also for use with the Rev-EXE.
Client.dll is located in Left 4 Dead 2\left4dead2\bin folder.
Ever since v2009 of the updates, a backup of the un-patched dll [client.dll.bak] is included for those who need it.

RevExe +RevEmu - [included in the latest rev-emu package above]
rev crew's cracked left4dead2.exe.
only for those who know what to do with it.
MediaFire

Stryder Loader 2.0.2 - OBSOLETE - do not use!
The Original L4D2 Fix.
Start game with bat file to play.
RapidShare - MediaFire


Stryder Alternate Loader 2.0.2 - OBSOLETE - do not use!
Alternative loader.
Start game with modded left4dead2.exe.
RapidShare - MediaFire

Mad creds and 'spect to the following:

the REVOLUTiON Crew
Patalete @ the PsyFamily
TheRINners
[Magi]Dan & [Wizard]Sean

Max20Characters
KKHafi
Knappy

Enjoy! and Good Luck!