To fix Undecember not launching, crashing, or freezing, you can try to update your graphics card, run the game as an administrator, or allow it in your antivirus.

You can also try disabling overlays/conflicting programs, repairing/verifying the game files, or updating Windows.

Undecember is an action role-playing game where players can combine a variety of skills and link runes.

Become a Rune Hunter and defeat powerful enemies to get new items.

Unlike other conventional growth systems, you can complete your own unique builds.

In this guide, you’ll learn how to fix Undecember not launching, crashing, freezing, or having a white/black screen.

Fix 1: Update your graphics card
Fix 2: Run Undecember as an administrator
Fix 3: Allow Undecember in your antivirg
Fix 4: Disable overlays/conflicting programs
Fix 5: Repair/verify the game files
Fix 6: Update Windows to the latest version

Fix 1: Update your graphics card

For Nvidia: Go to https://www.nvidia.com/en-us/geforce/geforce-experience/download/ > Download Now > open the app > sign up or log in > Drivers > Download.

For AMD: Go to https://www.amd.com/en/support > Download > open the app > follow the on-screen instructions to update your GPU.

Fix 2: Run Undecember as an administrator

Go to your Steam library.
Right-click Undecember > Properties > Local Files > Browse.

Right-click the Undecember app > Run as administrator.

Fix 3: Allow Undecember in your antivirus

Open the Windows settings > Privacy & Security > Windows Security > Virus & threat protection > Manage ransomware protection > Allow an app through Controlled folder access > Add an allowed app > Browse all apps > select the Undecember app > Open.

Open the Control Panel > System and Security > Windows Defender Firewall > Allow an app or feature through Windows Defender Firewall > Change settings > Allow another app… > Browse… > select the Undecember App > Add.

Turn off Real-time protection: Open the Windows settings > Privacy & Security > Windows Security > Virus & threat protection > Manage settings > Real-time protection > Off.

Fix 4: Disable overlays/conflicting programs

Go to your Steam library > right-click Undecember > Properties > Enable the Steam Overlay while in-game > Disable.

Open Steam > Steam > Settings > Downloads > Clear Download Cache.
Unplug the Logitech or Thrustmaster racing wheel.

End the task for Razer Synapse or MSI Dragon Center.

Close all of your tabs to free up RAM and relaunch the game.

Fix 5: Repair/verify the game files

Go to your Steam library.
Right-click Undecember > Properties > Local Files.

Select “Verify integrity of game files”.
Launch Undecember.

Fix 6: Update Windows to the latest version

Search for “Check for updates” using Windows Search.

Update Windows to the latest version.
Launch Undecember.

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