ComfyUI Prompt Has No Outputs Fix

Fix the ComfyUI 'prompt has no outputs' error by adding an output node, reconnecting the graph, unmuting nodes, and checking imported workflows for missing custom nodes.

If ComfyUI says prompt has no outputs, it usually means the graph does not end in a real output node.

The fastest fix is to make sure a Save Image or Preview Image node exists, is connected to the final image-producing path, and is not muted.

Fast Answer

What You See	What It Usually Means	First Fix
`prompt has no outputs` on a simple workflow	No output node exists	Add Save Image or Preview Image
Imported workflow shows red nodes too	Missing custom nodes broke the output chain	Install the missing nodes first
Output node exists but queue still refuses to run	The node is muted or disconnected	Unmute it and trace the link path backward
Workflow used to run before	A recent edit broke the last branch	Undo the last layout change or reconnect the final image path

What This Error Actually Means

ComfyUI is not saying your prompt text is wrong.

It is saying the workflow you queued does not currently produce a final output that ComfyUI can execute. In practice, that usually means one of these:

no Save Image node
no Preview Image node
the output node is disconnected
the output node is muted
imported red nodes broke the final branch

If you fix the graph structure, the error usually disappears immediately.

Step 1: Add a Real Output Node

The safest first test is to add one of these at the end of the workflow:

Save Image
Preview Image

Then connect it to the final image output from the sampler or decoder path.

If you are new to ComfyUI, use Preview Image to verify the graph works, then add Save Image once the workflow is stable.

Step 2: Trace the Final Branch Backward

Sometimes the output node exists, but it is not connected to the branch that actually generates the image.

Check this in order:

Start at Save Image or Preview Image
Follow the incoming link backward
Confirm it reaches the expected decode or image node
Confirm none of those nodes are red, greyed out, or disconnected

If the line path breaks anywhere, ComfyUI can show prompt has no outputs even though the canvas still looks busy.

Step 3: Unmute Disabled Nodes

Muted nodes are easy to miss in larger graphs.

If the final output node or a node right before it is muted, ComfyUI may treat the whole branch as non-runnable. Unmute the affected nodes, then queue again.

If you are not sure which branch is active, build the smallest possible working chain:

model loader
prompt encode
sampler
VAE decode
Preview Image or Save Image

Once that works, reconnect the rest of the workflow.

Step 4: Fix Missing Custom Nodes First

If you imported a workflow from another creator and see red nodes, the real problem may not be the output node itself.

The final branch may be broken because a required custom node never loaded.

Do this first:

Open ComfyUI Manager
Run Install Missing Custom Nodes
Restart ComfyUI
Reopen the workflow
Check whether the final output branch is now intact

If Manager itself is broken, use ComfyUI Manager Failed to Get Custom Node List Fix.

Step 5: Check the Workflow After Recent Edits

This error often appears right after:

deleting a preview node
replacing a sampler or decode branch
switching from one model format workflow to another
muting a section while testing
importing only part of a larger workflow

If the workflow used to run five minutes ago, do not reinstall ComfyUI first. Compare the current end of the graph with the last known working version.

This is also where saved workflow backups help. If you exported JSON before editing, you can compare the old graph and find the missing branch quickly. See How to Save a Workflow in ComfyUI.

Simple Working Output Chain

For a standard image workflow, the end of the graph should look roughly like this:

Sampler -> VAE Decode -> Save Image

Sampler -> VAE Decode -> Preview Image

If your graph does not end in something like that, ComfyUI probably has no output to run.

Common Cases That Confuse Users

"I can see nodes everywhere, so why does it say no outputs?"

Because ComfyUI cares about runnable output branches, not just node count. A large graph with no valid final output is still a graph with no outputs.

"I imported a workflow and only some nodes are red"

One missing custom node near the end can break the only output branch. Fix the missing nodes before judging the rest of the workflow.

"Preview works in screenshots online, but not in my copy"

The shared workflow may depend on models or nodes you do not have. The canvas layout can look complete while the backend path is broken.

When This Is Not Really an Output Problem

If you have a valid output node and the queue still fails, the next issue may be:

missing models
plugin import failure
dependency conflict
browser or frontend desync

Use these next:

How Wonderful Launcher Fits

This error is usually small by itself, but it often appears inside a bigger pattern: imported workflows, missing custom nodes, unstable environments, and repeated trial-and-error edits.

Wonderful Launcher helps when you want to:

keep known-good workflow versions
preserve working models and custom nodes
recover faster after plugin experiments
avoid rebuilding a half-working ComfyUI setup from scratch

If workflow changes keep breaking a previously stable setup, download Wonderful Launcher before the environment gets harder to recover.