Sandbox / Building Guide

Valheim

Detailed connection, admin, file, settings, mods, backup, wipe, and troubleshooting notes for Valheim dedicated servers.

Connect & First Checks

Before editing files

Use Join Game > Add Server or Steam favorites with IP:PORT.
Valheim often uses a game port plus adjacent query ports; use the exact panel connection address.
Server password must be at least 5 characters and cannot be the same as the server name.

Stop server before edits

Startup parameters	-name, -port, -world, -password, -public are common Valheim dedicated server settings.
worlds_local or worlds	World .db and .fwl files. Both are needed for a usable backup.
adminlist.txt	Permitted admin Steam IDs.
bannedlist.txt	Banned Steam IDs.
permittedlist.txt	Allowlist when permitted-list behavior is used.
BepInEx	Common mod loader folder for modded Valheim.

High-use values

-name	Server name.
-world	World file name without extension. Changing it loads/creates another world.
-password	Player password.
-port	Base game port. Panel controls final allocation.
-public	1 for public listing, 0 for private/unlisted.

Staff access

Add SteamID64 to adminlist.txt.
Restart server.
In-game admin commands require devcommands/admin status depending on current Valheim behavior.

Install carefully

BepInEx mods require server-side install and often client-side matching installs.
Keep server/client mod versions aligned.
After game updates, verify BepInEx and mods still support the current Valheim build.

Protect player data

Common tickets

Password rejected	Too short or same as server name.
World missing	Only .db or .fwl restored; both are required.
Version incompatible	Client/server or mods differ.
Server not listed	Check -public and use direct IP while browser updates.

Docs and sources