Valheim Version Mismatch and Update Problems

Valheim requires the server and every client on it to be running the same build. When they are not, the symptoms are all versions of the same thing: a friend cannot connect, the server has vanished from the browser, or the game refuses the join outright. This guide covers what those failures look like, how to tell a version problem from the four things that impersonate one, and what to do on an update day — including 9 September 2026, when Valheim 1.0 arrives and every client in the world updates at once.

The short version

Compare the version number in the bottom-right of the client's main menu against everyone else's. If they differ, the fix is an update on whichever side is behind, followed by a server restart. If they match, it is not a version problem — skip to the impostors.

The One Rule

Iron Gate stated it plainly when crossplay shipped: "make sure your game has the same patch version as your friends', or else connecting to each other might not work." The same applies between a client and a dedicated server.

That version number lives in the bottom-right corner of the main menu. It is the first thing to check and the fastest thing to check, and it settles most launch-week tickets in about fifteen seconds.

What the Error Actually Says

Here we are going to be careful, because half the guides on this subject quote error text nobody can find in the game.

Iron Gate has published only a little about the exact wording, and what they published is a bug report about it. Patch 0.220.3, released to the public test branch on 28 February 2025 and to the default branch on 4 March 2025:

"When trying to connect to a server using an incompatible version of Valheim, the correct message regarding incompatible version is now shown instead of a message regarding the host not allowing crossplatform on the server"

Two useful things fall out of that. First, Valheim does have a distinct incompatible version message, separate from its crossplay message. Second — and this is the trap — on builds before 0.220.3 a version mismatch could report itself as a crossplay problem. If you are on an old build, or reading an old forum thread, a message about the host not allowing cross-platform play is not proof that crossplay is the issue.

Earlier still, patch 0.214.2 of 13 March 2023 changed when you find out:

"If a server is unjoinable for version mismatch or other restriction this will shown when attempting to join a game from the server list immediately rather than having to wait for the game to load"

So on a current build, a version-mismatched server refuses you at the server list rather than after a loading screen.

Why we are not quoting the exact on-screen sentence

Valheim's connection errors are localised into fourteen languages and their wording has been revised across several patches — the changelogs repeatedly list "updated localization" alongside these fixes. Iron Gate does not publish the string table, so the sentence a player reads depends on their build, their platform and their language. Match on meaning, not on wording: if the message names a version, treat it as a version mismatch, whatever the exact phrasing.

Two strings we can give you verbatim, because they appear in Iron Gate's own documents:

• Game server connected — the line the server prints when it is genuinely accepting connections. Iron Gate's dedicated server guide: "When the Server program shows the message 'Game server connected' the Server is up and running, ready to accept connections." Anything before it is still setup.
• logging in to backend service — a client-side state, quoted in Iron Gate's patch 0.219.13 notes when they fixed a case where you could "infinitely get stuck" on it. More on that below.

Why the Server and the Clients Drift Apart

Because they are two different products with two different update paths, and this is the part most people get wrong.

Valheim's client and its Valheim Dedicated Server tool are separate Steam applications — app 892970 and app 896660. They are built together and released together, but they are not published in the same instant. For patch 0.221.12, the current live build, Steam's own application data shows the client's public branch updated at 19 February 2026, 08:07 UTC and the dedicated server's public branch at 20 February 2026, 08:39 UTC — a gap of just over a day. (Checked 19 August 2026; both are still on that build.)

Now stack the ordinary realities on top of that:

• Clients update themselves. Steam patches a player's game quietly in the background. They do not decide to update; they relaunch and are on the new build.
• A server updates when it restarts. The new files are fetched at boot, so a server that has been up for a week is still running whatever it started with.
• Your players are not one group. Some launched this morning and updated, some have not opened the game since Tuesday.

Which is why the classic shape of an update day is: a few players update immediately, cannot join, and report the server as broken — while the players who have not launched Steam yet are still on it happily.

The fix is a restart. Restart the server so it fetches the new build, then have the players who are behind relaunch their game.

Steam branches, and the one that catches a single player

If exactly one person is the odd one out and everyone else is fine, they are usually on a different branch rather than a different patch. Valheim's Steam application data lists these, on both the client and the dedicated server:

None of those need a password. The public test branch does: Iron Gate's patch posts give the access code as yesimadebackups, entered under Properties → Betas in Steam. A player who opted into the test branch months ago and forgot is a very common single-player mismatch — and Iron Gate has confirmed there is no public test branch for 1.0, so on 9 September the test branch is not where anyone should be.

Have them right-click Valheim in Steam → Properties → Betas and confirm it says "None".

Steam, Xbox, Microsoft Store and Consoles Do Not Land Together

Iron Gate's crossplay FAQ says the versions stay in step: "There's no difference between the versions. All versions of Valheim will continue to be updated at the same pace."

"Same pace" is not "same minute". Each storefront has its own certification and rollout, and Iron Gate does not publish a per-platform release schedule. Assume a window on any patch day — and on 1.0, a window across six platforms — during which some of your players have the new build and some do not.

What that means for a host is a piece of expectation management rather than a setting:

• Do not troubleshoot in the first hour. Wait until the update has actually propagated before you conclude anything is broken.
• Tell your players the server is updated once you have restarted it, so the ones still on the old build know the fix is on their side.
• Do not roll the server back to accommodate stragglers. You would then lock out everyone who did update, and a world saved on a newer build is not guaranteed to load on an older one — Iron Gate warned about exactly that when the Ashlands was on test: saves "might not be backwards compatible with older versions".

Four Problems That Look Like a Version Mismatch

1. The server is not on the crossplay backend

The single most common false positive, and it will be much more common after 1.0 puts PlayStation 5 and Switch 2 players in front of it.

Iron Gate's dedicated server guide, verbatim: "-crossplay — Runs the Server on the Crossplay backend (PlayFab), which lets users from any platform join. If you do not include this argument, the Steam backend is used, which means only Steam users can see and join the Server."

A server left on the default is invisible to every non-Steam player. On a hosted server this is the Crossplay field in the Startup tab; set it and restart. And remember the historical wrinkle above — on builds before 0.220.3 the two errors could be reported the wrong way round, so "it says something about cross-platform" is a reason to check both, not one.

Is Valheim Crossplay? covers the backend in full.

2. The password stops the server before it starts

This one is a masterpiece of misdirection, because the server appears to be down rather than misconfigured.

On a public server — and public is the default — Valheim refuses to start if the password is shorter than five characters, or if the password appears inside the world name or the seed. It does not boot and reject logins; it writes Error bad password: to the console and exits.

If your server "disappeared" right after you changed a setting, read the console from the top and look for that line before you blame the update. Getting started with your Valheim server and Valheim Server Settings and Launch Arguments both cover the rule.

3. The server list is just slow

A freshly started or freshly restarted server takes several minutes to appear in the community browser, and console players search that list rather than typing an address.

Confirm the server is actually up by joining it yourself with Join Game → Join IP before you conclude anything. Also check that Public is set to 1 — -public 0 makes a server join-by-IP only, which looks identical to "missing" from a player's side.

4. The join code changed

On a crossplay server, the Join code shown in the pause menu is regenerated every time the server restarts — including the nightly scheduled restart, and including the restart you just did to apply the update. A code shared yesterday will be rejected today.

The IP and port do not change. Share those for anything permanent and treat the code as a same-day invite.

Stuck on "Logging In to Backend Service"

This is a crossplay-backend problem rather than a version problem: the client cannot complete its login to Valheim's PlayFab backend, so it never gets as far as your server.

Iron Gate has acknowledged one specific cause of the hang. Patch 0.219.13, 29 October 2024:

"Fixed a bug where you could infinitely get stuck on 'logging in to backend service' if you had deleted your playfab account and subsequently lost internet"

That fix is long since live, so on a current build the remaining causes are on the player's side — the client cannot reach the backend at all. Worth trying, in order: relaunch the game, confirm the machine has internet, and retry in a few minutes in case the backend itself is having a moment. Related: patch 0.218.19 of 1 July 2024 records a fix to "prefer IPv4 over IPv6, fixing some issues with connecting to dedicated servers" — so on an old client, IPv6 is a known source of dedicated-server trouble.

Nothing you can change on the server fixes this one, which is worth knowing before you spend an hour on it.

Mods Blocking Startup After 1.0

After a big update, "the server will not start" and "the game will not launch" are usually mods, not the update.

Iron Gate's 1.0 FAQ sets the expectation: "Since we don't have any official mod support, we cannot guarantee that any mods will be functional when 1.0 releases." And because there is no public test branch for 1.0, no author gets to compile against the new build in advance.

Their guidance before the Ashlands update was specific, and it is the best template we have for 1.0:

"If you're using mods, it's therefore recommended that you disable them before you download the [update], otherwise the game will most likely not launch properly. To disable mods you will also need to remove BepInEx or any other mod loader, as they might try to load regardless."

Read that second sentence twice. Emptying BepInEx/plugins/ is not enough — the loader itself has to go.

On a hosted server: set Server Type to vanilla, restart, and confirm you get a clean boot and Game server connected. If that works, the update is fine and the mods were the problem. Put them back one at a time as authors ship rebuilds, checking BepInEx/LogOutput.log after each, and installing mods covers how to tell whether a mod is still maintained at all.

Client-side mods matter here too. If one player cannot launch their game while everyone else is fine, ask what is in their BepInEx folder before you touch the server.

Common Errors, and What They Actually Mean

Update-Day Runbook

Applies to any patch, and to 9 September in particular.

1. Back up before anything else. A manual snapshot, not just the scheduled one — see How to create a backup.
2. Run save or stop the server cleanly, so the world on disk is current.
3. Restart the server so it fetches the new build. Watch for Game server connected. If the version does not move, the dedicated server package may not have published yet — as above, that is a wait, not a fault, and restarting again later is the only fix.
4. Join it yourself before you tell anyone it is fixed.
5. Re-share the join code, because the restart changed it.
6. Tell your players the server is updated. Anyone still failing is behind on their own client, or on a beta branch.
7. Expect a mod-free few days. Run vanilla until authors catch up.
8. Give the storefronts time. Not every platform gets the update at the same moment, and you cannot make that go faster.

Valheim 1.0: What Changes for Server Owners covers the rest of the launch — the existing-world question, achievements, and what console players need.

FAQ

How do I check my Valheim version?

Bottom-right corner of the main menu. Compare it with another player's, and with what your server console printed at startup.

Why does my Valheim server say incompatible version after an update?

The server is still on the old build. Valheim servers fetch updates when they restart, so a long-running server keeps its old build indefinitely while clients update themselves in the background. Restart it.

Only one of my friends gets a version error. Why?

They are almost certainly on a different Steam branch — often the public test branch, opted into months ago. In Steam, right-click Valheim → Properties → Betas, and set it to None.

Will my server update itself for Valheim 1.0?

It fetches the new build at boot, so it updates when it next restarts. If you run a daily scheduled restart it will pick 1.0 up on its own — but back up first, and do the restart deliberately rather than letting the schedule surprise you.

Can I stay on an older version so my players do not have to update?

You can point Steam at a previous branch, and Iron Gate maintains several. It is a bad idea on an update day: you lock out everyone who did update, and a world saved on a newer build is not guaranteed to load on an older one.

Do Steam, Xbox and PlayStation get Valheim updates at the same time?

Iron Gate says all versions "continue to be updated at the same pace", but each storefront rolls out on its own schedule and no per-platform timetable is published. Expect a window on any patch day.

My server disappeared after I changed a setting. Is that a version problem?

Probably not. Read the console from the top: a password under five characters, or one that appears in the world name or seed, makes a public server exit at startup with Error bad password:.

Do mods cause version mismatch errors?

Not usually — a mod problem normally shows up as a failure to launch or a plugin error in BepInEx/LogOutput.log, not a version message. But after a big update, both happen at once, so clear the version question first and then test with Server Type set to vanilla.

What to Read Next

• Valheim 1.0: What Changes for Server Owners — the launch itself, worlds, mods and console players
• Managing your Valheim server — restarts, backups and keeping everything on one build
• Getting started with your Valheim server — first boot, connecting, and the password rule
• Valheim Server Settings and Launch Arguments — every launch argument Iron Gate documents
• Is Valheim Crossplay? PC, Xbox, PS5 & Switch 2 Explained — the two backends and who can see your server
• How to install mods for your Valheim server — BepInEx, server types and what breaks after an update

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