Verify Your Valheim Server Is Vanilla

Is your Valheim server actually vanilla?

"Vanilla" means the server loads no mods. On Valheim this is more subtle than it sounds, because the mod loader (BepInEx) can be installed but disabled, and plugins can be present in the plugins folder while the loader does not initialise them. From the panel's switch you may see "BepInEx off" while the actual binary still has plugin DLLs sitting on disk, and a crash loop can be triggered by a plugin that does not even load.

This page is the checklist for confirming your Valheim server is truly vanilla.

The three things that have to be true

1. The BepInEx loader is disabled or absent.
2. The plugins folder is empty (no leftover .dll files).
3. The startup log contains no plugin init exceptions.

All three. Customers who only check the first one are the ones who file tickets that start with "my vanilla server is crashing."

Check 1: the loader

BepInEx hooks into Valheim's startup by setting the Unity doorstop launcher option. On Supercraft servers this is exposed in the panel's Config tab as a toggle. If it is off, the launcher does not call BepInEx, and the game starts the way Iron Gate shipped it.

Toggle off in the panel, click Save and Restart. Done.

Check 2: the plugins folder

Open the File Manager and navigate to:

/home/u<port>/vlh/bin/BepInEx/plugins/

Every .dll in this folder is a plugin. If the folder contains any DLL files, your server has had mods installed at some point, even if BepInEx is currently disabled. Delete every .dll in the folder. If a subfolder exists, delete that too.

Leave the folder itself in place; the empty folder is harmless and BepInEx recreates it on next start anyway.

Why this matters even when BepInEx is off

BepInEx-off means the loader is not invoked, so the DLLs are not executed. They are still on disk. The moment you toggle BepInEx back on (or a future server update flips the launcher mode), every DLL in this folder is loaded again. People who flipped BepInEx off months ago to "go vanilla" but kept the plugins around get a surprise the next time they try to install something.

Check 3: the log

BepInEx writes its startup log to:

/home/u<port>/vlh/bin/BepInEx/LogOutput.log

Open this file in the File Manager or grep it from the Logs tab. A clean vanilla server has either no LogOutput.log at all (BepInEx never ran) or a log whose body is just the loader saying it found zero plugins. What you must not see:

• [Error : BepInEx] lines.
• System.Reflection.ReflectionTypeLoadException from a plugin assembly.
• Failed to load <PluginName> entries.

If you see any of these, the corresponding plugin is still being initialised and failing. That failure can crash the entire server. Go back to check 2 and delete the DLL named in the error, then restart.

"My doctor reports a BepInEx exception but I have no mods installed"

The Supercraft panel's diagnostic helper used to flag any line matching *Exception: in LogOutput.log as a real init failure. On a fresh Valheim install with the panel-default BepInEx scaffold present but no plugins, the loader's plugin-scan step writes a few exception-shaped lines during its empty-folder walk. The customer sees a clean server boot, plays for a while, comes back to the doctor tab, and gets told "BepInEx init exception."

This was a false positive. The current rule (v2, since the May 2026 patch) only fires when the exception names a non-builtin assembly - so a real plugin DLL that failed to load triggers the alert, but the loader's own empty-folder walk does not.

If you are seeing the warning on a vanilla server, three things to check before you assume anything is wrong:

1. Verify the plugins folder is actually empty. If a DLL is sitting there, the warning is legitimate. Follow Check 2 above.
2. Confirm a graceful shutdown line exists. Open LogOutput.log and grep for OnApplicationQuit. A line like [Info : Unity Log] Game - OnApplicationQuit at the end of the previous boot means the last run exited cleanly. That alone tells you the "exception" was not fatal.
3. Check the exception target. A real plugin failure names the assembly: [Error : BepInEx] *Exception: ... at FooMod.Plugin.Awake (). A loader-internal one looks like [Error : BepInEx] Exception while scanning ... with no plugin name. If you only see the second shape, the server is fine.

If the doctor flagged it but all three checks come back clean, the rule misfired. Open a support ticket with the doctor session link; we will look at the live log and confirm.

The clean-slate procedure

If you are not sure what is installed and you just want a guaranteed vanilla state, do this:

1. Click Stop in the panel.
2. In File Manager, delete the entire /home/u<port>/vlh/bin/BepInEx/ directory.
3. In the Config tab, set the BepInEx toggle to off (if your panel exposes one).
4. Click Start.
5. Watch the Logs tab: a vanilla Valheim startup ends with Game server connected and a Steam handshake. No BepInEx lines should appear.

This leaves your world saves alone (those live under /home/u<port>/vlh/saves/) and only removes the modloader and its plugins.

"But I want to keep BepInEx installed for later"

Reasonable: BepInEx itself is harmless when the plugins folder is empty. Leave the loader in place, empty the plugins folder, restart. LogOutput.log will report zero plugins, and the server runs vanilla. Later, when you want to add a mod, drop its .dll into the plugins folder and restart. No reinstall needed.

Player check

Vanilla Valheim does a server-client version handshake on join. A truly vanilla server will accept any vanilla Valheim client of the same game version. If a player still gets kicked with an "incompatible version" error after you have followed everything above, the mismatch is on their end (they probably have BepInEx installed locally with a mod that changes a synced value). Have them check their own BepInEx/plugins/.

Ready to run vanilla without surprises? See Valheim plans. BepInEx toggle is one click; the panel keeps modded and vanilla worlds cleanly separated.