Install and Play Minecraft Modpacks with ATLauncher

ATLauncher Overview

ATLauncher is a Minecraft launcher built for players who want modpacks without manually lining up every mod, library, and loader version by hand. It can install packs from several supported sources, create separate instances, import packs from URLs or files, and manage multiple Minecraft accounts.

That makes it useful whether you are trying a quest pack, a tech-heavy kitchen sink pack, or something that adds enough creatures to make nighttime a poor career choice. This guide covers installing ATLauncher, adding your account, downloading a modpack, importing a pack, and fixing common problems.

Download and Install ATLauncher

Start by downloading the version of ATLauncher that matches your operating system. Windows, macOS, and Linux each have their own installer options, so choose the one meant for your device.

1. Open the official ATLauncher download page and select the download for your OS.

1. Save the file somewhere easy to find, then open it.
2. Follow the installer prompts and choose the directory where ATLauncher should be installed.

1. Click Finish when the setup is complete. The launcher should open automatically.
2. Wait for ATLauncher to download updates, then choose your language when prompted.

1. Click Save to finish the setup.

Add Your Minecraft Account

Before launching a modpack, ATLauncher needs a valid Minecraft account. For most players, this means signing in with a Microsoft account.

1. Open ATLauncher and select Accounts from the right side menu.

1. Sign in with Microsoft, or enter your username and password if that option applies to your account.
2. Enable Remember Password if you want ATLauncher to keep the login saved, then click Add.

1. Confirm any Microsoft or launcher prompts that appear. Once finished, ATLauncher should switch to the added account.

Install a Modpack from ATLauncher

The simplest method is to install a pack directly inside ATLauncher. This works well when the modpack is already listed under one of the supported services.

1. Select Packs from the menu on the right side of ATLauncher.
2. Choose a source or category from the list on the left.

1. Use the search bar, Minecraft version filter, or other fields to find the modpack you want.

1. When you find the pack, click New Instance.

1. Enter a name for the instance if you want a custom label, then click Install. Avoid changing the version unless you specifically need an older or newer build.

1. When the install finishes, click OK and open the Instances tab.
2. Press Play on the new instance to start the modpack.

Import a Modpack

If you already found a pack elsewhere, ATLauncher can import it from a supported URL or from a local file. This is useful for packs from platforms such as CurseForge, Modrinth, or MultiMC, as long as the format is compatible.

1. Open the Instances area.
2. Click Import in the top left.

1. Paste the modpack URL, or click Browse and select a `.zip` or `.mrpack` file from your computer.

1. Click Import and wait while ATLauncher checks and downloads the needed files.
2. If the import is accepted, name the profile and click Install.

1. Return to Instances and click Play on the imported pack.

Troubleshooting ATLauncher Modpacks

The Modpack Is Hard to Find

Use the extra search filters before assuming the pack is missing. Try selecting a specific Minecraft version, changing the source category, or searching for a shorter version of the pack name.

If it still does not appear, look up the pack on a supported modpack site and use the import option instead. Some modpacks are not available through every launcher, so a missing listing does not always mean the pack is gone.

Importing Fails

Import failures usually come from an unsupported URL or an incorrectly packaged file. ATLauncher supports imports from specific services, including CurseForge, Modrinth, and MultiMC. Random download pages may not work, even if the modpack itself is valid.

For local files, make sure the pack is a proper `.zip` or `.mrpack` file. If you are compressing the files yourself, use a tool such as 7-Zip or WinRAR and include the correct pack contents, not an extra folder layer that hides everything inside.

The Modpack Crashes

Crashes after installation are often caused by low memory. Open ATLauncher's settings and increase the RAM available to Minecraft, but do not assign all of your system memory. Leaving your computer with no breathing room is a reliable way to create a different problem.

If memory is not the issue, try reinstalling the instance with a different modpack version. Delete the broken instance, return to the pack installer, and choose another build from the version selector. For server play, also make sure your client modpack version matches the server version. HolyHosting servers should use the same modpack build as the players connecting to them.

Related Guides

• How to manually install modpacks
• How to change your Minecraft server version
• How to update a modpack on Minecraft servers
• Minecraft modpack server setup tips