How to Install Mods on Your Valheim Server (BepInEx)

What is BepInEx?

BepInEx is the modding framework for Valheim. It must be installed on the server before any mods can be used.

BepInEx Version — Important

Valheim uses the Unity IL2CPP build (since the Ashlands update). This requires BepInEx 6.x (IL2CPP build), not the older BepInEx 5.x.

Using the wrong BepInEx version will cause the server to fail silently or crash on startup. If your Pterodactyl egg has BepInEx pre-installed, verify it is version 6.x.

Installing BepInEx

If BepInEx is not pre-installed on your egg:

1. Download the correct BepInEx 6.x IL2CPP build for Linux
2. Upload and extract it into your server root directory via SFTP
3. Ensure the startup command uses the BepInEx wrapper script instead of the default launcher
4. Restart your server and check the console for BepInEx loading messages

Installing Mods

1. Find mods on Nexus Mods or Thunderstore
2. Download the mod .dll file
3. Upload it to BepInEx/plugins/ on your server
4. Restart the server

Client Requirements

Not all mods are server-side only. Many Valheim mods must be installed on both the server and all connecting clients. Server-side-only mods (world modifiers, loot tables) may not require client installation. Check each mod description.

Most players use r2modman (Thunderstore Mod Manager) to manage their client-side mods.

Troubleshooting

• Server crashes after installing BepInEx — You likely have the wrong version. Verify you are using BepInEx 6.x IL2CPP, not BepInEx 5.x
• Mods not loading — Check BepInEx/LogOutput.log for error details
• Players disconnected after adding mods — Those players need the same mods installed on their client