Valheim error codes and crash fixes
Every error, crash and connection failure we have a fix for, one page per code. Before the fix, each page says whether the problem is your machine or the studio's servers — because if it's theirs, no amount of verifying game files will help, and the only useful answer is whether it's happening right now.
Things you can fix
Crashes, install faults and driver conflicts. Find your symptom, work the steps in order, stop when it launches.
Valheim "Failed to connect" when joining a server (fix)
Joining a friend's world or a dedicated server ends in "Failed to connect", or sits on "Connecting" and never loads the world.
Valheim "Incompatible version" error: client vs server (fix)
You enter the server password and are disconnected with an "Incompatible version" message instead of loading in.
Valheim crossplay not working: can't join, PlayFab error (fix)
A friend on another platform can't see or join your world with the join code, or a dedicated server started with -crossplay reports a PlayFab connection error and Steam and console players can't get in.
Things you cannot
Queues, capacity limits and login failures. These are server-side — every page below links back to live status rather than a fix you can perform yourself.
Valheim world corrupted, missing or LOAD ERROR after 1.0 (fix)
A world that saved normally now shows as corrupted, is missing from the world list, or its seed shows LOAD ERROR, and restoring backups fails or brings back an older state.
Valheim items marked "cheated" without using cheats (fix)
Ordinary drops, crafted items or items from chests show as "cheated" even though nobody used dev commands.
Valheim items lose upgrade levels on item stands after 1.0 (fix)
Weapons, armour or fish on an item stand or armour stand come back at a lower upgrade level, or without their variant, after the world is loaded in 1.0.
How these are graded
Every fix step carries a label. Confirmed means players demonstrably got back in with it, or the studio said so directly.Reported means it worked for some people and not others. Unconfirmed means it's circulating and there's no evidence either way yet. The distinction is the point — a page that lists five fixes with equal confidence costs you an evening.