Valheim server will not start: what to check

Open the Console, start the server, and read the last lines before it stops. Each cause below prints its own message. Match yours, then follow the link for the fix.

Match the message

Lines that do not stop the server

• [playnhost] mods: could not apply ... and [playnhost] Mods could not be applied: see above: a mod could not be installed, and the game starts without it. See Valheim mod did not load on your server.
• [playnhost] PlayNHost tools are off for this start: ...: the game starts without the tools this time. See The Valheim players card says PlayNHost Tools are not answering.

It starts, but the badge never says Online

The badge turns Online when the Console prints Opened PlayFab server or Opened Steam server. A new world takes about 20 seconds more to generate, a first start takes about a minute, and a start that downloads an update or mods takes longer. Wait for those lines. If they never come, look at the lines before for one of the messages in the table.

It restarts by itself, then stops

When the game quits on its own, for example after a world load failure, the panel restarts it once, and then it stays Offline. The message in the Console is the cause.

Settings to check

• World Name and Server Password: How to change your Valheim server name and password.
• Server Name up to 53 characters: with crossplay on, a longer name makes the login fail and the server stops.
• After a game update on a modded server, check your mods: How to update mods on your Valheim server.

Get help

Include the last 50 to 100 lines of the Console. Use Share log to make a link: How to read your Valheim server console. See How to fix a server that will not start and What to include in a ticket.