Note: If you have the original Steam releases of the Doom games (not the bfg edition) you are up-to-date and do not need to bother reading this.
As you may or may not be aware, several versions of Doom were released between 1993 and 1995 due to bugs being found, and features being added. You can find all of the history for the releases here
.The latest version of all of the iwads are final version "1.9"
If you need to check which version of any IWAD you have, you can use this utility by Russell: http://russell.slipgate.org/iwadverifier.php
There are patches released by id software that will update your installation of Doom and Doom 2 to the latest version, however you have to have the original full install which includes the exe, wad, and all corresponding files. Additionally they only run in DOS
. But fear not, as patching utilities to simplify the process have been made over the years!http://www.doomgate.de/content/files/ladopato/index_en.html
This iwad patcher will take any of your doom iwads and update them to the latest version, all you have to do is point it at what file you want to patch. Doom 3: BFG Edition users, go ahead and revert your iwads BACK to version 1.9. The instructions are on the site page.
For other platforms, you can check out the Java patcher by the same author. http://www.doomgate.de/content/files/ladopato/javapatcher/JIWadPatcher.html
It is a bit more complicated to use, but not too much!
Thanks to Peter "Phenex2" Vaskovic for releasing these great utilities to help the Doom community.