How to Solve Custom Node List Failure in ComfyUI

Have you ever opened up ComfyUI, excited to generate something amazing, only to be greeted by a “Custom Node List Failure” message? Ugh! Nothing ruins your creative flow faster than an annoying error. But don't worry — you're not alone, and yes, it can be fixed (without pulling your hair out).

TL;DR (Too long, didn't read)

This error usually happens when ComfyUI can't load a custom node properly. The most common reasons? A missing file, bad code, or outdated add-ons. Fixing it is usually as simple as checking your folder, installing any missing requirements, or updating your custom node. Breathe easy — you're about to become a mini ComfyUI mechanic.

What is the “Custom Node List Failure” in ComfyUI?

Let’s break it down simply. ComfyUI works like LEGO blocks for generating images. Each block is a node. People create custom nodes to add cool features. When something goes wrong with those custom nodes, ComfyUI throws a tantrum and refuses to load properly.

Here’s what that failure really means:

• ComfyUI tried to load a custom node.
• It couldn’t because something’s broken, missing, or outdated.
• The whole node list goes MIA or loads with errors.

Why Does This Happen?

Several reasons could be behind this pesky error. Some are super simple, and some need a little more digging. Here's a list of the usual suspects:

1. Missing Dependencies: Python Packages not installed yet.
2. Typos in Code: Even a tiny mistake can break the node.
3. Version Mismatch: Your ComfyUI is too new or too old for the custom node.
4. Folder Issues: Wrong location or a bad folder name ruins everything.
5. Conflicting Add-ons: Two nodes don’t play nice together.

Okay, How Do I Fix It?

Now we're talking! Let’s go step-by-step and patch it up. Don’t skip — even if you think you know it already!

1. Check the Log File

ComfyUI usually logs everything it tries to load. Go to the folder where ComfyUI is installed and look for a file named console_log.txt or just check the terminal output after launch.

• Open that file or window.
• Search for words like “ERROR” or a node name that appears broken.
• Screenshot or copy the error message — it helps a LOT.

2. Find the Trouble Node

If the error message includes a line like:

Failed to import custom_nodes/my_custom_node/__init__.py

Then bingo! That’s your troublemaker. Go to that folder and check:

• Is the __init__.py file present?
• Does it contain proper Python code?
• Are all the required packages installed?

3. Install Missing Python Packages

Many custom nodes require specific packages to work — like torch, numpy, or PIL. You can install them by opening a terminal and running:

pip install -r requirements.txt

If there’s no requirements.txt file, check the custom node’s GitHub page. The needed packages are usually mentioned there.

4. Update Your Custom Nodes

Sometimes a simple update does the trick! If you're using git to install nodes:

cd custom_nodes/the_node_folder  
git pull

If it was a manual download, go grab the latest version from the creator’s page and replace the old files. Don't forget to restart ComfyUI after.

5. Verify Folder Structure

The folder structure matters more than you'd think.

Make sure your folders look like:

ComfyUI/
├── custom_nodes/
│   ├── my_custom_node/
│   │   ├── __init__.py
│   │   └── other_files.py

No mismatched names like “my-node” or “node (1)” — those will break things!

6. Test With Only One Node

Sometimes it’s not just one node breaking — it’s combinations of them. Try this:

1. Move all folders out of custom_nodes except one.
2. Launch ComfyUI.
3. If it works, start adding nodes back one by one.

This helps isolate the problematic node or conflict.

7. Update ComfyUI

If you haven’t updated ComfyUI in a while, now’s the time:

git pull

Updates often improve compatibility with newer custom nodes. Save your workflow first, just in case!

8. Ask the Community

You’ve tried everything and it’s still not working? Join the conversation:

• ComfyUI Discord
• GitHub Issues page of the node
• Reddit or other AI communities

Share your error logs and what you’ve tried. People are usually eager to help!

Bonus Tip: Use a Separate Environment

Creating a fresh Python environment just for ComfyUI can help avoid package mess:

python -m venv comfy_env  
source comfy_env/bin/activate  
pip install -r requirements.txt

This keeps everything neat and avoids messing with your system Python.

Prevention Tips

Now that you’ve fixed it, here’s how to avoid it in the future:

• Only install trusted nodes. Avoid random zip files.
• Read the README. Always check for dependencies.
• Test new nodes one at a time. Don’t go install-happy!
• Backup your ComfyUI folder. Especially before updates.

Still Feeling Stuck?

Don't worry. Sometimes, troubleshooting is more frustrating than it needs to be. Custom nodes add tons of magic, but yes — a little chaos too. It's all part of joining the ComfyUI wizarding world.

Once you get the hang of fixing these errors, you’ll feel like a tech superhero. 🦸‍♂️🦸‍♀️

So go ahead. Tame that faulty node, restart ComfyUI, and get back to creating your next AI masterpiece!