Assetto Corsa Is Obsolete V1.16.3 Is Required

If you own a legitimate copy of Assetto Corsa on Steam, your game should be v1.16.3. If it isn't, the files are corrupt.

Steam will scan every file, detect that your acs.exe is wrong, and download a fresh, clean v1.16.3 executable. Warning: This will sometimes break Custom Shaders Patch. You will need to reinstall CSP after this step.

In Content Manager, before you click "Join," look at the server details pane. Many modern servers explicitly list:

If the server explicitly bans CSP versions above 0.1.80, you have two choices: install a portable instance of the game for legacy mods, or find a better server. Modern sim racing has moved on; servers stuck on 0.1.80 are going extinct. assetto corsa is obsolete v1.16.3 is required

Many users report that CSP versions after 0.1.80 cause the "obsolete" error with certain Porsche and Mercedes mods.

You have three solutions, ranging from the simple to the nuclear. Start with #1 and work your way down.

After updating, your game version appears: If you own a legitimate copy of Assetto

Once you see 1.16.3 (or higher), the error should disappear. Happy racing!

When Kunos stopped updating the game, the modding community—led by the legendary modder Ilja "x4fab" Jusupov—kept it alive with the Custom Shaders Patch. CSP doesn't just add rain or pretty lights; it rewrites huge chunks of the game’s executable in real-time (via a technique called "DLL injection").

As CSP evolved, modders started building features that required specific CSP versions. Eventually, server hosts began using a feature within CSP that checks the client’s reported game version. Steam will scan every file, detect that your acs

Here is the catch: Modern versions of CSP (specifically versions 0.2.0 and above) trick the game into reporting a fake version number to the server to ensure compatibility. Specifically, many server configs look for 1.16.3 because that was the last stable "vanilla" version before CSP fundamentally altered the netcode.

If your CSP is too new, too old, or misconfigured, the server sees your version mismatch and kicks you with the "obsolete" message.