Go ahead and install the 1.0.8.0 Update and extract all of its contents to your main GTA:IV game directory and replace when asked.Go to your main GTA:IV directory and delete ‘PlayGTAIV.exe’.Make sure you have a Steam Retail version of the game and not some other version, as I have not tested any other version(Such as the Rockstar Game Launcher version).Install GFWL if you don’t already have it set up.
How to play GTA:IV Multiplayer after March 19th Complete Edition Update GTA:IV MP Support Downgrading(1.0.8.0) / Text Version. Look in the pinned comments of that video as well if you are having issues with serial key BS This works for the Steam Edition and Rockstar Games Launcher Edition. After looking around for a bit, I found a super easy tutorial in order to downgrade your GTA:IV Complete Edition to 1.0.7.0 in order to allow for modding support etc.
