"Incompatible version" means your Valheim client and the server are on different game versions — or, on a modded server, your BepInEx mods don't match. Here is how to fix it for both vanilla and modded setups.
Quick answer
"Incompatible version" means your Valheim client and the server run different game versions — usually because one side updated after a patch. Update the server to the current build and restart it, then update your game. On a modded server, BepInEx and every mod must match on both sides, so sync them with r2modman or Thunderstore.
Vanilla: update both sides
After a Valheim patch, the server must update too. If your client updated but the server didn't (or vice-versa), you get this error. Update the server to the current build and restart it.
Modded: match BepInEx & mods
On a modded server, the client needs the same mods at the same versions as the server. A mod that updated on one side causes an incompatible-version mismatch. Use a mod manager (r2modman/Thunderstore) to sync — see Valheim server not showing.
Update the server first, then players, then rejoin. Restart the server so it actually runs the new version before testing.
Which case are you?
"Incompatible version" has three common causes — match your situation to the fix:
| Your setup | Likely cause | Fix |
|---|---|---|
| Vanilla server | Client and server on different game builds | Update the server to the current build and restart |
| Modded (BepInEx) | A mod updated on one side only | Sync the exact mod set/versions with a mod manager |
| Steam vs Game Pass | Crossplay setting mismatch | Match the server's crossplay setting to how you connect |
Step-by-step fix
- Note whether the server is vanilla or modded — the fix differs.
- Vanilla: update the dedicated server to the current build.
- Modded: open your mod manager and sync to the server's exact mod list and versions (not just "latest").
- Restart the server so it actually loads the new version.
- Have players update their side, then rejoin — server first, players second.
Client and server (and all mods) must be the same version. Update the server, sync mods, restart, rejoin.
Cause 3: crossplay or platform mismatch
If the server runs with crossplay settings different from your client (Steam vs Xbox/Game Pass), you can hit a version-style rejection even on the same build. Confirm the server's crossplay setting matches how you're connecting.
How to prevent version mismatches
- Turn on auto-update for the server where possible.
- Announce updates to players before restarting.
- Pin mod versions in a shared modpack/profile so nobody drifts.
- Check the Valheim patch notes before a big session.
Related errors
If the server does not show up at all, see Valheim server not showing. Setting one up from scratch? See how to make a Valheim server and the best Valheim mods. For a general timeout instead of a version error, see connection timed out.
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