If your modpack isn't in Modpack Installer, upload it yourself: zip your mods folder, upload it, and remove anything that only belongs on a player's own game.
How to install it
- On your PC, find the modpack's
modsfolder (inside your CurseForge or Modrinth instance) and compress it to a.zip. - Open Files and upload that zip into the mods directory.
- Extract it so the files land directly in the mods folder.
- Open Console and start the server. If it crashes, the log names the mod causing it.
- Remove any client-side-only mods (visual, sound, or UI mods), they don't belong on a server and will block startup.
- If the crash log names a missing dependency, install that too.
- Restart, confirm it reaches Online, then connect. You need the identical modpack installed locally to join.
Client-only mods are the leading cause of a server that won't boot after a custom modpack upload. Rendering, sound, and UI mods never belong in the server's mods folder.
Still stuck?
Server won't start: see How to Read the Crash Log or Fix "Missing Dependency" and Mod Conflict Errors.
Pack is actually in the catalog: use How to Install a Modpack instead, it's much simpler.
Not sure you have enough RAM for this pack: check How Much RAM Does Your Modded Server Need? before uploading.
Still broken: open a support ticket with your Console crash log attached, our team can trace the exact mod that's failing.
Did this solve it?
If you are still stuck, our team can look at your server directly.