Installing mods on your tModLoader server

Two ways to add mods to a tModLoader server: uploading .tmod files to the Mods folder and enabling them, and where those files come from in the first place.

3 min read · Updated Sep 24, 2026 · By GuavaHost Team

tModLoader mods are single files with a .tmod extension. Your server keeps them in a folder called Mods, and a small text file called enabled.json decides which of them actually load. Once you understand those two things, installing mods is straightforward.

Where .tmod files come from

The easiest way to collect mods is through your own tModLoader client:

1. Launch tModLoader and open Workshop, then Download Mods to open the in-game Mod Browser.
2. Download each mod you want on the server.
3. Open the Workshop menu and use Open Mods Folder, or browse to Documents/My Games/Terraria/tModLoader/Mods on your computer, to find the .tmod files.

Each file is named after the mod's internal name, for example CalamityMod.tmod.

Upload the mods to your server

1. Take a snapshot first on the Backups page. Restoring overwrites current files, so a backup means you can undo a bad mod cleanly.
2. Open the Files tab and go into the server's Mods folder. If it does not exist yet, start the server once so tModLoader creates it, or create it yourself with New folder.
3. Upload your .tmod files into that folder with Upload files, or drag them onto the file list. The browser takes files up to 100 MB each, so for bigger mods use SFTP (a secure way to move files between your computer and your server) with the free client FileZilla. The SFTP details are on the Settings tab under Connection details.

Enable the mods

Uploading a mod does not turn it on. tModLoader only loads the mods listed in enabled.json.

1. In the Mods folder on the Files tab, click enabled.json to open it. If there is no enabled.json yet, make one on your computer and upload it, because the Files tab has no button for a new empty file.
2. It is a plain list of the mods' internal names in quotes, for example:

[
  "CalamityMod",
  "ThoriumMod"
]

1. Add the internal name of each mod you uploaded, exactly as the .tmod file is named but without the .tmod part. Keep the commas and brackets correct.
2. Click Save.
3. Press Restart at the top of the server page and watch the log on the Console tab. tModLoader lists each mod as it loads, so you can confirm they all came up.

Some GuavaHost setups expose mod options under Startup settings on the Settings tab instead. If yours has a field for mods there, you can set them in that field and let the server handle the download on boot, rather than uploading by hand.

Remember the golden rule

Every player has to run the same enabled mods, at the same versions, as the server. After you change the server's mods, tell your players to update and enable the matching list in their own Manage Mods menu, or they will not be able to join.

Troubleshooting

• Mod uploaded but not loading: it is probably missing from enabled.json, or the name is misspelled. The name must match the .tmod filename exactly, and it is case sensitive.
• Server crashes on boot after adding a mod: two mods may conflict, or one needs a dependency mod you did not upload. Check the Console log for the mod it names, then remove or add mods to fix it.
• Broken enabled.json: a missing comma or bracket stops the whole list loading. Compare it against the example above.
• Want to undo everything: restore the snapshot you took on the Backups page.

Still stuck? Jump into our Discord at discord.gg/GuavaHost and the team will help you out.

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• mods
• tmod
• files
• install

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