Panel Haus Docs
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Neural Forge

Neural Forge Troubleshooting

Common Neural Forge errors and how to fix them.

Connection issues

"Connection refused" or "Test failed"

  1. Is ComfyUI running? Check http://localhost:8188 in your browser.
  2. Did you use --listen? Without it, ComfyUI only accepts connections from 127.0.0.1.
  3. Is cloudflared running? Check the terminal for errors.
  4. Did the tunnel URL change? Temporary URLs change every restart, so copy the new one.

CORS errors in the browser console.

△ Watch out CORS errors mean ComfyUI was not started with --enable-cors-header. Stop ComfyUI and restart it with the flag: python main.py --listen --enable-cors-header

WebSocket connection fails. Cloudflare Tunnels support WebSocket by default. If you see WebSocket errors:

  • Make sure you are using https:// (not http://) for the tunnel URL in Panel Haus.
  • Check that ComfyUI's WebSocket port matches the HTTP port (default: both 8188).

Generation errors

400 Bad Request, "Node not found."

ℹ Missing custom nodes A Panel Haus workflow uses a custom node that is not installed in your ComfyUI. The error message tells you which node is missing.
  • DetailDaemonSamplerNode, install: cd custom_nodes && git clone https://github.com/Jonseed/ComfyUI-Detail-Daemon
  • BEN2 / RMBG nodes, install: cd custom_nodes && git clone https://github.com/Loewen-Hob/rembg-comfyui-node-better

Always restart ComfyUI after installing custom nodes.

RMBG background removal, "process_res" error. This happens when the BEN2 model file is missing or corrupted.

  1. Check that the model file exists in ComfyUI/models/ (location depends on the node pack).
  2. Re-download the model if it is corrupted or zero-byte.
  3. Restart ComfyUI.

Performance issues

Slow generation or timeouts. Cloudflare Tunnels add minimal latency (about 10 to 50ms). If generations are slow:

  • Check your GPU utilization. Is it maxed out?
  • Larger images take longer. Try a smaller resolution first.
  • The first generation after startup is always slow (the model loads into VRAM). Later ones are faster.

"Bad gateway" (502). ComfyUI crashed or is not running. Check the ComfyUI terminal for errors, then restart it.

Out of VRAM.

△ Watch out If ComfyUI crashes or generates black images, you have run out of GPU memory. Try: close other GPU-intensive apps (games, other AI tools); use a smaller model (SD 1.5 instead of SDXL); generate at a lower resolution (512×512 instead of 1024×1024); or add the --lowvram flag to ComfyUI's launch command.

Tunnel URL changed. If using the temporary quick-start tunnel, the URL changes every restart. Either copy the new URL into Neural Forge settings each time, or set up a named tunnel for a permanent URL.