Setup guide
Install the pack
Seven steps, written for someone who has never installed a modpack. About ten minutes, most of it waiting on downloads.
Download Indigo
Indigo is a single .mrpack file. It contains no mods itself, only the exact list your launcher should install, so it is small and always matches the server.
Prefer to skip the file? Prism Launcher’s Add Instance → Import also takes a link. Copy this one and paste it in:
+ Verify the download
SHA-256 of Indigo-0.3.0.mrpack:
344580a270c822c4542f1c43e769dfb6f4075e9a8e63e27576d90514542255c9
Install a launcher
A launcher is the program that installs Minecraft, the mod loader and the mods, then starts the game. We recommend Prism Launcher: free, open source, signs in with your normal Microsoft account.
Prism Launcher is the launcher application. Indigo is the server and modpack. You install Prism once, then import Indigo into it.
Alternative: Modrinth App. The CurseForge app is not recommended for this pack.
Import Indigo
In Prism Launcher:
Add Instance → Import → Browse → Indigo-0.3.0.mrpack → OK
Prism installs Minecraft 1.21.1 and NeoForge 21.1.248, then downloads each mod and checks it against the pack. Wait for the progress window to finish.
In the Modrinth App: create a new instance from file and pick the downloaded .mrpack, or drag it onto the window.
Java 21
Indigo requires Java 21. Prism Launcher can download it for you during setup. If the instance complains about Java, point it at Java 21 here:
Edit Instance → Settings → Java
Need a copy? Adoptium Temurin 21 is free.
Memory
Give the game enough memory, and no more than that:
Edit Instance → Settings → Memory
- Recommended
- 4096 MB
- With shaders
- about 6144 MB
Giving Minecraft most of your computer’s RAM makes it stutter, not faster.
Whitelist
Indigo is whitelist-only during the beta. Before you try to join, send the owner or an admin your exact Minecraft Java username, spelled and capitalised the way it shows in game. You need a real Minecraft: Java Edition account.
Connect
Launch the Indigo instance. In Minecraft:
Multiplayer → Add Server
Server address:
- No port needed.
- Voice chat is included in the pack and connects automatically to the same address.
- Press V in game to choose your microphone.
Troubleshooting
“You are not whitelisted on this server”
Your exact username has not been added yet. Send the server owner or an admin your exact Minecraft Java username, then try again once they confirm.
Mod rejections, or a red screen listing mismatched mods
Your instance no longer matches the server. Re-import the official Indigo pack into a fresh instance and do not replace or add gameplay mods by hand.
“Incompatible FML modded server”
Wrong Minecraft version, wrong NeoForge version, or the wrong instance selected. Use the official Indigo pack: it installs Minecraft 1.21.1 with NeoForge 21.1.248.
The game crashes while joining
Before changing anything by hand, re-import a clean Indigo pack into a new instance and try again. Most joining crashes come from an instance that drifted.
Java errors, or the instance will not start
Check that Java 21 is selected for the instance (Edit Instance → Settings → Java in Prism Launcher). Older or newer Java versions will not run this pack.
Nobody can hear me in voice chat
Press V in game to open the voice chat settings and pick the right microphone. Voice connects to the same address as the game, so if you can play, voice should reach the server too.
Still stuck? Ask in the Discord and include the exact message you see. Back to Play.