Fix Unturned Asset Bundle Version Mismatch

The "Asset bundle version mismatch" error is one of the most common issues in Unturned multiplayer. It occurs when the server and client have different versions of the same mod, preventing players from connecting.

Understanding the Error

When you see this error, it means:

• The server has a different version of a mod than you do
• The mod's asset bundle doesn't match between server and client
• Steam failed to update the mod properly on one side

Solution 1: Server-Side Fix (For Server Owners)

Force Server Mod Update

1. Stop your Unturned server
2. Navigate to your server's workshop directory
3. Delete the entire Workshop folder
4. Restart the server - it will automatically re-download all mods

Update WorkshopDownloadConfig.json

1. Check your WorkshopDownloadConfig.json file
2. Ensure all mod IDs are correctly listed:

{
    "File_IDs": [123456789, 987654321, 555666777],
    "Priority": 0
}

3. Restart the server to trigger mod downloads

Solution 2: Client-Side Fix (For Players)

Resubscribe to Problematic Mods

1. Unsubscribe from the mods causing the error
2. Restart Unturned completely
3. Clear your workshop cache (see below)
4. Re-subscribe to the same mods
5. Launch Unturned and let mods download

Clear Workshop Cache

1. Close Unturned completely
2. Navigate to: Steam\steamapps\workshop\content\304930
3. Delete the folders for problematic mods
4. Restart Steam and Unturned

Solution 3: Advanced Troubleshooting

Identify Problematic Mods

To find which mod is causing the issue:

1. Check the server console for error messages
2. Look for mod names in the error dialog
3. Ask the server owner for their mod list
4. Compare versions in the Steam Workshop

Verify Mod Versions

1. Check the Workshop page for each mod
2. Look for "Updated" dates
3. Ensure server and client have the same version
4. Some mods show version numbers in descriptions

Preventing Future Version Mismatches

For Server Owners

• Set up a regular restart schedule (daily or weekly)
• Use mod collections to ensure consistency
• Test mods after updates before going live
• Keep a backup of working mod configurations

For Players

• Enable auto-updates for Unturned and workshop items
• Don't manually modify workshop files
• Follow server mod update announcements
• Clear cache periodically if you experiment with mods

Troubleshooting Table

Using Mod Collections

The best way to prevent version mismatches is through Steam Collections:

1. Create a collection with all your server's mods
2. Share the collection link with players
3. Update the collection when mods change
4. Players automatically get the correct versions

When All Else Fails

If you've tried everything and still get version errors:

1. Contact the server owner - they may need to update specific mods
2. Check the mod's Steam Workshop comments for known issues
3. Try joining without certain mods to isolate the problem
4. Consider using a fresh Unturned installation

Keep your Unturned server and client mods synchronized to prevent version mismatch errors and ensure smooth multiplayer gameplay.