No downgrade needed
Install it next to the copy of Grand Theft Auto IV you already own. Nothing gets patched back or replaced, and singleplayer keeps working exactly as it did.
HappinessMP is a multiplayer modification for Grand Theft Auto IV. Install it, pick a server, play.
Works with the current Steam and Rockstar releases of GTA IV. Windows 10 and 11.
Install it next to the copy of Grand Theft Auto IV you already own. Nothing gets patched back or replaced, and singleplayer keeps working exactly as it did.
HappinessMP builds on the network code that shipped with the game. Sync holds up under load, and traffic, pedestrians and police carry on around you.
Servers bring their own scripts and rules. Freeroam, racing, roleplay, or something nobody has built yet.
Select an image to see it full size.
One file, no dependencies. It finds your Grand Theft Auto IV installation on its own.
Choose one from the server list, or type in an address a friend sent you.
HappinessMP starts the game and drops you straight into the server. Your singleplayer saves stay untouched.
The download is free. For questions, servers and people to play with, there is the Discord.
Want to run your own server? Read the server manual