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Running without GUI

This guide will help you test if Leela Chess Zero is working correctly by running it without any chess GUI program.

Step-by-Step Instructions

Step 1: Find the lc0 file

  1. Open File Explorer (the folder icon in your taskbar, or press Windows key + E)
  2. Navigate to the folder where you installed Leela Chess Zero
    • This is usually in a folder like C:\Lc0\ or wherever you extracted the files
  3. Look for a file named lc0 (it will show as type “Application” or “Windows Application”)
    • Note: You might not see the .exe extension - that’s normal in Windows

Step 2: Run lc0 directly

  1. Double-click on the lc0 file
  2. A black window (Command Prompt) should open
    • Don’t worry if it looks intimidating - this is normal!
    • You should see some text appear, possibly including version information

Step 3: Test the engine

  1. In the black window, type exactly: go nodes 1000
  2. Press Enter
  3. Wait for the program to respond (this may take a few seconds)

Step 4: Check the results

Look at what appears in the black window:

✅ Good signs (everything is working):

  • You see lines starting with “info” showing search progress
  • You see a line starting with “bestmove” followed by a chess move (like “bestmove e2e4”)
  • No error messages appear

❌ Problem signs (something needs fixing):

  • Error messages appear (often in red text)
  • The program crashes or closes immediately
  • You see messages about missing files or networks
  • Nothing happens after typing the command

Step 5: Take a screenshot or copy the text

Before closing the program, you should save what you see for getting help:

Option 1 - Take a screenshot:

  1. Press Windows key + Shift + S (this opens the snipping tool)
  2. Click and drag to select the black window
  3. The screenshot will be saved to your clipboard

Option 2 - Copy the text:

  1. Right-click anywhere in the black window
  2. Select “Select All” from the menu
  3. Right-click again and select “Copy”
  4. The text is now copied to your clipboard

Step 6: Exit the program

  • Type quit and press Enter, OR
  • Simply close the black window by clicking the X button in the top-right corner

What to do next

  • If everything worked correctly: Your Leela Chess Zero installation is fine, and any problems are likely with your chess GUI setup
  • If you saw error messages: Post your screenshot or copied text in the #help channel of the Lc0 Discord server for assistance

Getting Help

If you encountered problems:

  1. Join the Lc0 Discord server
  2. Go to the #help channel
  3. Paste your screenshot or the copied text from the black window
  4. Describe what you were trying to do and what went wrong

Common Issues

  • “Network not found” errors: You may need to download a neural network file
  • “CUDA/OpenCL errors”: Your graphics card drivers may need updating
  • Program won’t start: You might be missing required system files (like Visual C++ redistributables)

Tip: The screenshots and copied text will help the community diagnose your specific issue much faster than just describing the problem

Last Updated: 2025-08-08