If some of the game system files have been damaged, this should fix the problem. Note: this can also help you fix the error 'Failed to Start Game: Missing Executable' that sometimes keeps Valheim from starting up.
Instead of re-installing, you can try and repair them by verifying the integrity of game files. If the previous method didn't fix Valheim, then your game files may be corrupt. If you can't run the game, you should try to force windowed mode and change the resolution by doing the following: If Valheim won't start, you may have a non-native resolution set in the game, which is different from your display's resolution. Valheim is very sensitive to the display resolution settings. Valheim Won't Launch or Start Fix Method 1: Force Windowed Mode If the problem persists, then follow the steps below. These simple steps are essential before launching any game, not just Valheim.
It's also worth making sure your anti virus software isn't blocking the game. Before trying out all the methods listed below, be sure to update Windows and your graphics card/video card drivers.
