How to Troubleshoot and Solve ComfyUI Issues

​

Quick Issue Diagnosis

If you’re experiencing any of these issues, there is a high likelihood that it is caused by custom nodes:

• ComfyUI crashes or won’t start
• “Failed to import” errors in console/logs
• UI completely breaks or shows blank screen
• “Prompt execution failed” errors not related to memory issues
• Missing nodes that should be available/installed

​

Is It a Custom Node Problem?

Most ComfyUI issues are caused by custom nodes (extensions). Let’s check if this is the case.

​

Step 1: Test with all custom nodes disabled

Run ComfyUI with all custom nodes disabled:

cd path/to/your/comfyui
python main.py --disable-all-custom-nodes

cd path/to/your/comfyui
python main.py --disable-all-custom-nodes

cd ComfyUI
python main.py --disable-all-custom-nodes

.\python_embeded\python.exe -s ComfyUI\main.py --disable-all-custom-nodes  --windows-standalone-build
pause

.\python_embeded\python.exe -s ComfyUI\main.py --disable-all-custom-nodes  --windows-standalone-build
pause

.\python_embeded\python.exe -s ComfyUI\main.py --disable-all-custom-nodes

Results:

• ✅ Issue disappears: A custom node is causing the problem → Continue to Step 2
• ❌ Issue persists: Not a custom node issue → Report the issue

​

Step 2: Find the Problematic Custom Node

We’ll use binary search to quickly find which custom node is causing issues. This is much faster than testing nodes one by one.

​

Option A: Using Comfy CLI (Recommended)

If you have Comfy CLI installed, you can use the automated bisect tool to find the problematic node:

# Start a bisect session
comfy-cli node bisect start

# Follow the prompts:
# - Test ComfyUI with the current set of enabled nodes
# - Mark as 'good' if the issue is gone: comfy-cli node bisect good
# - Mark as 'bad' if the issue persists: comfy-cli node bisect bad
# - Repeat until the problematic node is identified

# Reset when done
comfy-cli node bisect reset

The bisect tool will automatically enable/disable nodes and guide you through the process.

​

Option B: Manual Binary Search

If you prefer to do the process manually or don’t have Comfy CLI installed, follow the steps below:

​

How Binary Search Works

Instead of testing each node individually (which could take hours), we split the nodes in half repeatedly:

8 nodes → Test 4 nodes → Test 2 nodes → Test 1 node ✓

Example with 8 nodes:
1. Test nodes 1-4: Issue persists ✓ → Problem in remaining nodes 5-8
2. Test nodes 5-6: Issue gone ✓ → Problem in nodes 7-8  
3. Test node 7: Issue persists ✓ → Node 7 is the problem!

This takes only 3 tests instead of testing all 8 nodes individually.

​

Binary Search Process

​

Create Temporary Folders

# Create backup and temporary folder
mkdir "%USERPROFILE%\custom_nodes_backup"
mkdir "%USERPROFILE%\custom_nodes_temp"

# Backup everything first
xcopy "custom_nodes\*" "%USERPROFILE%\custom_nodes_backup\" /E /H /Y

# Create backup and temporary folder
mkdir "%USERPROFILE%\custom_nodes_backup"
mkdir "%USERPROFILE%\custom_nodes_temp"

# Backup everything first
xcopy "custom_nodes\*" "%USERPROFILE%\custom_nodes_backup\" /E /H /Y

# Create backup and temporary folder
mkdir ~/custom_nodes_backup
mkdir ~/custom_nodes_temp

# Backup everything first
cp -r custom_nodes/* ~/custom_nodes_backup/

# Create backup and temporary folder
mkdir /content/custom_nodes_backup
mkdir /content/custom_nodes_temp

# Backup everything first
cp -r /content/ComfyUI/custom_nodes/* /content/custom_nodes_backup/

​

Find the Problematic Node

1. List your custom nodes:

   • Windows
   • macOS/Linux
   • Cloud like Colab

   dir custom_nodes

   dir custom_nodes

   ls custom_nodes/

   ls /content/ComfyUI/custom_nodes/

2. Split nodes in half:

   Let’s say you have 8 custom nodes. Move the first half to temporary storage:

   • Windows
   • macOS/Linux
   • Cloud/Colab

   # Move first half (nodes 1-4) to temp
   move "custom_nodes\node1" "%USERPROFILE%\custom_nodes_temp\"
   move "custom_nodes\node2" "%USERPROFILE%\custom_nodes_temp\"
   move "custom_nodes\node3" "%USERPROFILE%\custom_nodes_temp\"
   move "custom_nodes\node4" "%USERPROFILE%\custom_nodes_temp\"

   # Move first half (nodes 1-4) to temp
   move "custom_nodes\node1" "%USERPROFILE%\custom_nodes_temp\"
   move "custom_nodes\node2" "%USERPROFILE%\custom_nodes_temp\"
   move "custom_nodes\node3" "%USERPROFILE%\custom_nodes_temp\"
   move "custom_nodes\node4" "%USERPROFILE%\custom_nodes_temp\"

   # Move first half (nodes 1-4) to temp
   mv custom_nodes/node1 ~/custom_nodes_temp/
   mv custom_nodes/node2 ~/custom_nodes_temp/
   mv custom_nodes/node3 ~/custom_nodes_temp/
   mv custom_nodes/node4 ~/custom_nodes_temp/

   # Move first half (nodes 1-4) to temp
   mv /content/ComfyUI/custom_nodes/node1 /content/custom_nodes_temp/
   mv /content/ComfyUI/custom_nodes/node2 /content/custom_nodes_temp/
   mv /content/ComfyUI/custom_nodes/node3 /content/custom_nodes_temp/
   mv /content/ComfyUI/custom_nodes/node4 /content/custom_nodes_temp/

3. Test ComfyUI:

   python main.py

4. Interpret results:

   • Issue persists: Problem is in the remaining nodes (5-8)
   • Issue gone: Problem was in the moved nodes (1-4)

5. Narrow it down:

   • If issue persists: Move half of remaining nodes (e.g., nodes 7-8) to temp
   • If issue gone: Move half of temp nodes (e.g., nodes 3-4) back to custom_nodes

6. Repeat until you find the single problematic node

​

Visual Example

Let’s walk through a complete example with 8 custom nodes:

📁 custom_nodes/
├── 🔧 ComfyUI-Manager
├── 🎨 ComfyUI-Custom-Scripts  
├── 🖼️ ComfyUI-Impact-Pack
├── 🔄 ComfyUI-Workflow-Component
├── 📊 ComfyUI-AnimateDiff-Evolved
├── 🎭 ComfyUI-FaceRestore
├── ⚡ ComfyUI-Advanced-ControlNet
└── 🛠️ ComfyUI-Inspire-Pack

Round 1: Move first 4 to temp

• Test → Issue persists ✓
• Problem is in: ComfyUI-AnimateDiff-Evolved, ComfyUI-FaceRestore, ComfyUI-Advanced-ControlNet, ComfyUI-Inspire-Pack

Round 2: Move 2 of the remaining 4 to temp

• Test → Issue gone ✓
• Problem is in: ComfyUI-Advanced-ControlNet, ComfyUI-Inspire-Pack

Round 3: Move 1 of the remaining 2 to temp

• Test → Issue persists ✓
• Found it! ComfyUI-Inspire-Pack is the problematic node

​

Step 3: Fix the Issue

Once you’ve identified the problematic custom node:

​

Option 1: Update the Node

1. Check if there’s an update available in ComfyUI Manager
2. Update the node and test again

​

Option 2: Replace the Node

1. Look for alternative custom nodes with similar functionality
2. Check the ComfyUI Registry for alternatives

​

Option 3: Report the Issue

Contact the custom node developer:

1. Find the node’s GitHub repository
2. Create an issue with:
   • Your ComfyUI version
   • Error messages/logs
   • Steps to reproduce
   • Your operating system

​

Option 4: Remove or Disable the Node

If no fix is available and you don’t need the functionality:

1. Remove the problematic node from custom_nodes/ or disable it in the ComfyUI Manager interface
2. Restart ComfyUI

​

Reporting Issues

If the issue isn’t caused by custom nodes, refer to the general troubleshooting overview for other common problems.

​

For Custom Node-Specific Issues

Contact the custom node developer:

• Find the node’s GitHub repository
• Create an issue with your ComfyUI version, error messages, reproduction steps, and OS
• Check the node’s documentation and Issues page for known issues

​

For ComfyUI Core Issues

• GitHub: ComfyUI Issues
• Forum: Official ComfyUI Forum

​

For Desktop App Issues

• GitHub: ComfyUI Desktop Issues

​

For Frontend Issues

• GitHub: ComfyUI Frontend Issues