Common Issues

MU Online Server Client Guide
Welcome to our MU Online server! This guide will help you get started and troubleshoot common issues when running the client. Please read this document carefully before seeking support, as it contains solutions to most common problems.

📥 Downloading and Installing the Client
After Download ensure all files are extracted properly and that no files are blocked by your antivirus software.

⚠️ Common Issues and Fixes

1. Client Does Not Open
   Cause: Missing or blocked files.
   Solution: Ensure that your antivirus or Windows Defender hasn’t deleted or blocked any files. Add the MU Online folder to Windows Defender's exclusion list (instructions below).

2. Disconnected After Login
   Cause: Incorrect game version or unstable internet connection.
   Solution:
   Make sure you are using the latest client version. Run Launcher.exe to get the latest update.
   Disable any VPNs or proxies, as they may interfere with the connection.

3. Black Screen After Launch
   Cause: Outdated drivers or incompatible settings.
   Solution:
   Update your graphics card drivers.
   Run the client as Administrator.
   If using a laptop with dual GPUs, ensure the high-performance GPU is selected for the client.

4. Game Crashes or Lags
   Cause: System resources or compatibility issues.
   Solution:
   Ensure your system meets the game's minimum requirements.
   Lower the game settings in game options or use built in anti-lag system (Shift + 0-9)
   Close unnecessary background applications.

5. Font Issues (Squares in-game or missing text)
   Install ARIALUNI.TTF font located in this Useful folder

6. Make sure you have Visual C++ Redistributable installed
   https://aka.ms/vs/17/release/vc_redist.x64.exe

7. Anti Virus deleting files
   In case Anti Virus has deleted main.exe or other file from Game folder you can delete cVersion file from Data folder and run Launcher.exe, it will apply the latest patch again.
   ⚠️ Make sure to add Game folder to Anti Virus exclusions before that.

🛡️ Adding MU Online to Windows Defender Exclusions
Sometimes anti virus falsely marks some files and deletes them, you can add mu folder to exclusions - run Exclude.bat or manually follow the steps below
Some antivirus software, including Windows Defender, may mistakenly flag MU Online files as threats. Follow these steps to add the game folder to Windows Defender’s exclusion list:
Open Windows Security by searching for it in the Start Menu.
Navigate to Virus & threat protection.
Under the Virus & threat protection settings, click Manage settings.
Scroll down to Exclusions and click Add or remove exclusions.
Click Add an exclusion and select Folder.
Locate and select your MU Online installation folder (e.g., "C:\Games\mueterny.com Full Client").
Confirm the addition, and you’re done!
For other antivirus programs, refer to their respective user manuals to exclude the MU Online folder.

🛠️ Additional Tips
Always run the game client as Administrator to avoid permission issues.
Ensure your system has the latest version of DirectX and Microsoft Visual C++ Redistributables.
If issues persist, try reinstalling the client or contact support through our Discord server.
📞 Need Help?
If you encounter any issues not covered in this guide, feel free to reach out to our support team:

Support: Support
Discord: Join our community Discord
Email: support@mueterny.com

Happy gaming!