Help

Press More info, then Run anyway.

The installer and the app are signed, but with REDLINE’s own certificate, not one from a certificate authority that Windows already trusts. SmartScreen shows this warning for any installer whose publisher it can’t vouch for yet. Only download REDLINE from redlinemod.com/download.

No. Assetto Corsa EVO’s own physics engine drives a converted car, the same as Kunos’ cars, and nothing in the game is overridden. What the converter brings across is the car’s data from its Assetto Corsa files: weight, engine curves, gearing, suspension, brakes, aero and electronics, turned into Assetto Corsa EVO’s format. Tyres start from an Assetto Corsa EVO tyre of the matching type and take the car’s own tyre values where Assetto Corsa EVO models them the same way. Anything Assetto Corsa doesn’t describe comes from a Kunos car of the same class. Every value’s source is in the car’s build report. More on the What converts page.

Into Assetto Corsa EVO’s own mods folder in your Saved Games, which the game reads by itself:

• Cars (converted, or installed from the Store): Saved Games\ACE\mods\content\cars\<car id>. Converted cars’ ids start with ac1_.
• Liveries from the Livery Studio or the Store: Saved Games\ACE\ExternalLiveries. Skins converted with a car go into that car’s own folder.
• Setups: Saved Games\ACE\Car Setups.

Saved Games is in your Windows user folder (C:\Users\<you>\Saved Games). If yours has been moved, for example to OneDrive, point REDLINE at it with Settings › Change locations.

REDLINE itself installs to %LOCALAPPDATA%\Programs\Redline Studio and keeps its settings, licence, cache and engine file in %LOCALAPPDATA%\Redline Studio.

It never modifies the game’s archive (content.kspkg) or its .exe. Steam’s own files stay as Steam installed them.

It does write a few small files of its own into the game’s install folder: redline_runtime.cfg, redline_bootrace_tune.cfg, trackmap_state.cfg and modloader_debug.flag, plus mods\redline_session_setup when you set fuel or tyres for a session.

When you start the game from REDLINE, it loads its engine file (redline.dll) into the game. That file is signed, and REDLINE checks the signature when it downloads it and again before every launch; an unsigned or altered file is never loaded. This is what runs the in-game features, such as quick launch and the fuel and telemetry options. Start the game from Steam and nothing of REDLINE’s is loaded, but the cars and liveries it installed are still there, because they live in the game’s own mods folder.

The game checks every car a server runs, so a modified car can only join a server that allows it.

REDLINE compares the game’s build with the build its engine file was made for. If they don’t match, it doesn’t load the engine file. It shows this notice instead:

Assetto Corsa EVO updated. REDLINE’s in-game features are paused until REDLINE supports this build — usually within a day. Everything else keeps working.

Launching still works: the game starts normally, without the in-game features. Your cars, liveries and setups are unaffected. When an engine file for the new build is published, REDLINE downloads it by itself and tells you it is ready. You don’t need to reinstall anything.

Right now: Works with Assetto Corsa EVO 0.9.1 (7 Sep 2026 build).

PRO adds the Assetto Corsa car and livery converters, saving your own liveries from the Livery Studio, and the Showroom for cars REDLINE built. Painting, installing and using liveries stays free, as does everything else in the app.

To get it, pledge Stage 2 (£5 a month) or Stage 3 on Patreon, then link Patreon in the app under Settings › Account. PRO is added to your licence key once the pledge has been charged; a free trial doesn’t count. Stage 1 supports the work but doesn’t include PRO.

PRO belongs to your licence key, not to one PC. At the moment it stays on the key after a pledge ends; a payment that is refunded or disputed removes it.

• Interface updates download in the background, are checked against their signature and apply the next time you open REDLINE. There is nothing to click.
• Engine file updates (support for a new game build) download by themselves, as above.
• App updates are offered in the app. Press Install & restart: REDLINE downloads the installer, checks its signature, installs it in the background and reopens with a note that it was updated. There is no prompt and no setup window. Updating from 1.3.0 shows one last administrator prompt, because 1.3.0 installed to Program Files; the update moves REDLINE to your user folder.

What changed in each version is on the changelog.

First remove anything you don’t want to keep from inside REDLINE, so its folders go with it: converted cars from Build › Convert from AC1 (Uninstall on the car), and Store downloads from the Downloads tab.

Then uninstall Redline Studio from Windows Settings › Apps. That removes the program from %LOCALAPPDATA%\Programs. These stay, and you can delete them by hand:

• %LOCALAPPDATA%\Redline Studio: settings, licence, cache and the engine file.
• Cars and liveries still in Saved Games\ACE\mods and Saved Games\ACE\ExternalLiveries. The game loads whatever is there, with or without REDLINE, so check before deleting: other mods may live there too.
• In the game’s install folder: redline_runtime.cfg, redline_bootrace_tune.cfg, trackmap_state.cfg, modloader_debug.flag and mods\redline_session_setup. The game doesn’t need any of them.

The REDLINE Discord is the quickest. You can also email support@redlinemod.com. Say which REDLINE version you have and what you were doing.