BirdNET-Analyzer GUI Startup Error (Code 503) on Windows 11

[G-auravSingh]

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🐛 Bug Report

Description

The BirdNET-Analyzer GUI application fails to launch on Windows 11. It opens a console window, briefly attempts to start the Gradio-based web interface, and then crashes with a traceback indicating a failure to access the local Gradio API endpoint.

The error message specifically points to a 503 Service Unavailable status on the localhost port.

Traceback / Error Message

Traceback (most recent call last):
  File "__main__.py", line 3, in <module>
  File "birdnet_analyzer\gui\__init__.py", line 8, in main
  File "birdnet_analyzer\gui\utils.py", line 822, in open_window
  File "C:\Users\Aura7.0\AppData\Local\Programs\BirdNET-Analyzer\_internal\gradio\blocks.py", line 2681, in launch
    raise Exception(
Exception: Couldn't start the app because 'http://127.0.0.1:7860/gradio_api/startup-events' failed (code 503). Check your network or proxy settings to ensure localhost is accessible.

Steps to Reproduce

1. Download the latest Windows installer (e.g., BirdNET-Analyzer-X.X.X-win_amd64.exe).

2. Install the application to the default location.

3. Attempt to launch the BirdNET-Analyzer GUI via the desktop shortcut or executable.

4. The application fails immediately with the traceback above.

Expected Behavior

The BirdNET-Analyzer GUI should launch successfully and open the web interface in the default browser or a dedicated application window.

Environment

Detail | Value -- | -- Operating System | Windows 11 Home Windows Version | 24H2 (OS Build 26100.6901) Processor (CPU) | (AMD Ryzen 7 4000 Series)

Troubleshooting Performed

I have attempted the following steps, but the issue persists:

1. Checked for Port Conflicts (7860): Verified that no other common application (like a local server or Docker) is running.

2. Firewall/Antivirus: Temporarily disabled Windows Defender Firewall and/or my third-party antivirus (specify which one) to rule out blocking.

3. Run as Administrator: Tried launching the application by right-clicking and selecting "Run as administrator."

4. Reinstall: Uninstalled and reinstalled the application using the latest available installer.

5. Visual C++ Redistributable: Ensured the latest Microsoft Visual C++ Redistributable (x64) is installed.

[Josef-Haupt]

Are you using a VPN or proxy? People had similar issues in the past, see this comment for possible solution.