To add mods to your Valheim server you install the BepInEx modding framework, then drop each mod's .dll file into the BepInEx/plugins folder and restart.
What BepInEx is
BepInEx is a modding framework that loads plugins into the game so mods can run. Almost every Valheim mod on Thunderstore and Nexus is built for it, so it is the foundation you install before anything else.
Check whether BepInEx is already installed
If you chose the Valheim + BepInEx server type, it is ready to go. Open the Files tab and look for a BepInEx folder in the server root containing plugins, config, and core. If it is there, skip to uploading your mods. If it is not, install it first, either through a mod option on the Startup tab if your server has one, or by uploading the BepInEx pack for Valheim. Take a snapshot on the Backups tab before you start.
Where mods go
- Plugin files with a .dll extension go in BepInEx/plugins. You can make subfolders inside it, since BepInEx scans them all.
- Config files generate automatically in BepInEx/config after the first run, and that is where you tweak a mod's settings.
- The load log is BepInEx/LogOutput.log, which tells you what loaded and what failed.
Install a mod step by step
- On the Backups tab, create a snapshot.
- Download the mod (Thunderstore is the easiest source) and unzip it.
- On the Files tab, open BepInEx/plugins and upload the .dll, plus any folder the mod ships with.
- Restart the server from the Console tab.
- Watch the Console or LogOutput.log for a line confirming the mod loaded, such as Loading [ModName].
Client mods vs server mods
Many mods must be installed on both the server and every player's PC, with matching versions. Some quality of life and admin mods only need to run on the server. Always read the mod's page to see which it is, because a version mismatch will stop players joining.
Dependencies and config
Some mods need a helper library first, such as Jotunn or HookGenPatcher. Install those dependencies into BepInEx/plugins as well. To change how a mod behaves, edit its file in BepInEx/config and restart.
Troubleshooting
- Server will not start after a mod: restore your snapshot, then remove the offending .dll.
- Mod not loading: check LogOutput.log for errors and confirm the mod matches your Valheim version.
- Players cannot join: everyone needs the same client side mods at the same version.
Still stuck? Jump into our Discord at discord.gg/GuavaHost and the team will help you out.