Instance Management

Create, edit, rename, and delete ComfyUI instances in Comfy Desktop

Comfy Desktop lets you manage multiple ComfyUI instances from the Chooser view.

Instance Types

Comfy Desktop supports four types of instances. Each type appears on its card and in the title bar; Tracked instances share the Standalone icon.

Type	Icon	Description
Standalone	💻	A self-contained ComfyUI instance created by Comfy Desktop. Includes bundled Python, automatic updates, and full snapshot support. This is the default when you click New Instance.
Cloud	☁️	A Comfy Cloud instance. Requires a Comfy Cloud account. Cloud instances run on Comfy’s servers and are billed separately.
Remote	🌐	Connects to a ComfyUI instance running on another machine on your network. Configure the remote host and port during setup.
Tracked	💻	Tracks an existing ComfyUI installation (Git clone or portable). Uses the same icon as Standalone. You manage updates manually. See Tracking an Existing Installation.

The image below labels the key actions available for each instance card:

1. New Instance: Create a brand new ComfyUI instance. See Creating a New Instance. You can also create an instance from a snapshot file.
2. ⋮ Menu: Click the three-dot icon to open the action menu for an instance. Right-clicking the card opens the same menu.
3. Manage: Open the Manage panel to configure the instance (path, launch args, model directories, environment variables). See the Manage page.
4. Duplicate Instance: Copy a standalone installation, with its own Python environment and custom nodes. See Duplicating an Instance.
5. Show in Finder, Show in Explorer, or Show in Folder: Open the installation folder in your file manager. The name follows your operating system.
6. Export Snapshot: Export the instance’s newest snapshot to a file you can share. See Share a Snapshot.
7. Restore Snapshot: Revert the instance to a previous snapshot. See the Snapshots page.
8. Uninstall: Permanently delete the instance and all its files from disk. See Uninstalling an Instance.

The menu also lists actions that only appear in certain states: Stop while the instance is running, Update when a new ComfyUI version is available, Migrate to Standalone for an installation you can migrate, and Create Build for a local instance you can publish to a workspace. Forget is not part of this menu; it sits in the Manage panel, see Uninstalling an Instance.

Creating a New Instance

Click the + card (top-left) in the Chooser view to add a new ComfyUI instance.

1. Create a New Instance

   Windows

   macOS

   Linux

   1. Name: The name of your instance. The default is “ComfyUI”.
   2. Public Builds: The recommended option. A standard ComfyUI install built for your detected hardware. Select Managed Builds to install a Build from one of your workspaces instead (see Workspaces and Builds), or Remote Connection to connect to a ComfyUI instance running on another machine.
   3. Release: The release channel to install. Stable (Recommended) is preselected.
   4. Hardware: Comfy Desktop detects your GPU and preselects the matching build (NVIDIA, AMD, Intel Arc (XPU), or CPU). Each option shows the ComfyUI version, the Python version, and the download size.
   5. Install Location: Where ComfyUI is installed. On Windows, it’s strongly recommended to use an SSD and avoid the root of the C: drive. The field shows free space on the drive and an install size estimate when Comfy Desktop knows it.

   If free space looks low, the wizard shows a Low Disk Space dialog. Choose Continue Anyway, or cancel and pick another path.

   

   Comfy Desktop also refuses folders it cannot install into. It checks the folder as soon as you pick one with Browse…, explains the problem under Install Location, and keeps Continue disabled until the folder is one it can use:

   • Inside Comfy Desktop’s own files: the application folder, its bundled resources, its data folder, and on Windows its updater caches. Those files are replaced when the app updates, so an installation there would be deleted. On macOS this covers anything inside the Comfy Desktop app bundle.

   • Inside OneDrive (Windows): cloud sync slows down a large Python environment and can corrupt files while they upload.

   • Inside a shared models, input, or output folder: installing there can corrupt the files every instance shares. See Storage.

   • Inside another instance’s folder: the two installations would conflict and can corrupt data.

     

   On a machine with an NVIDIA GPU, the NVIDIA build also checks the driver version. If the detected driver is older than 580, Comfy Desktop shows an Update NVIDIA Driver dialog with the detected version and the recommended minimum. Continue Anyway installs with the current driver.

2. Installing

   

   Comfy Desktop handles the rest. The progress screen runs a stepper: finished stages get a check, the active stage shows a spinner with a live detail line (percent, transfer speed, or file name), and the next stage waits below it. When the install finishes, the same stepper continues into the first launch, so the rows carry on with Starting ComfyUI and the startup stages.

   Stage	What it does
   Downloading ComfyUI	Fetches the ComfyUI bundle for the hardware you selected.
   Unpacking the install	Unpacks the bundle into the install folder.
   Set up environment	Creates the instance’s own Python environment and copies the prebuilt packages into it, which writes several gigabytes.
   Clean up environment	Removes packages the instance does not need, writes the environment configuration, fetches version tags, and records the instance’s first snapshot.
   Update to latest stable	Moves ComfyUI to the release channel you picked and installs its Python requirements, which can take an hour or more on a cold machine.

   An install created from a snapshot does not auto-update, so its stepper skips the last stage and shows the two restore stages instead.

   When you picked a starter template, its models download in the background during the stages above, so the install does not wait for them. The stepper then ends with Downloading template models once ComfyUI has started, and that row stays until the files finish. Select Skip & open ComfyUI on that screen to open the instance right away; the transfer keeps running in the downloads tray.

3. Choose a Template

   

   Once the installation is complete, Comfy Desktop opens the template library where you can pick a workflow template to get started.

   Templates that download models need enough free space for those files. If the drive cannot hold a template’s models, the wizard blocks that choice. Pick a lighter template or free space. On very small disks, the template step may be skipped entirely.

Tracking an Existing Installation

If you already have a ComfyUI installation (either manually set up from the Git repository or downloaded as a portable version), you can add it to Comfy Desktop without creating a new one.

Open the ☰ menu in the title bar and select Add Existing Instance.

1. The ☰ menu button in the top-left corner of the title bar.
2. Add Existing Instance: Opens the dialog that tracks an existing ComfyUI installation.

Detecting Your Installation

In the dialog, click Browse… and select the installation folder. Comfy Desktop probes the folder and fills in the rest of the dialog. The Detected type dropdown lists what it found:

• Standalone: A Comfy Desktop installation. The probe looks for a standalone-env directory and ComfyUI/main.py.
• Portable: A Windows portable build. The probe looks for python_embeded, either in the folder you selected or in a folder directly inside it.
• Git Clone: A clone of the ComfyUI repository. The probe looks for a .git directory.
• Legacy Desktop: An installation of the older ComfyUI Desktop app, recognized by its models/, user/, and .venv directories. See Migrate from Legacy Desktop.

If the probe finds nothing, the dropdown reads No known install detected. Select the folder that holds the installation itself, not a parent or unrelated folder.

Confirming the Detected Installation

After the probe finishes, the dialog shows what it found. Check the paths before you track the installation.

• Install location: The folder you selected. Click the path to open it, or Browse… to pick another one. For a portable build, point at the folder that contains python_embeded.
• Name: How the instance is listed in the Chooser. The dialog suggests a name.
• Detected type: Which kind of installation the folder holds.
• Version, Repository, and Branch: Shown for a Git clone.
• Virtual Environment: Shown for a Git clone when Comfy Desktop finds one, in .venv, venv, .env, or env with a pyvenv.cfg file inside. Browse… points the instance at a different environment.

Click Track Install to add the instance. No files are moved or copied.

Track vs Standalone

The key difference between a Tracked (Add Existing Instance) installation and a Standalone installation is how updates are managed:

Aspect	Tracked (Existing)	Standalone
Updates	No automatic updates: in a Git clone you pull and reinstall yourself, and a portable build is replaced by a newer one	Built-in automatic updates
Python	Uses an existing Python environment (.venv, python_embeded, etc.)	Bundled Python, automatic dependency management
Isolation	Shares the existing path and environment	Fully self-contained, isolated installation
Snapshots	Not supported	Snapshot support available
Use case	Already have ComfyUI set up and customized	Fresh install from scratch

Note: Comfy Desktop runs a tracked installation with its existing Python environment and does not reinstall ComfyUI or manage its packages. Snapshot capture runs only for Standalone instances.

Launching, Stopping, and Restarting an Instance

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Launching an Instance

Click an instance card in the Chooser to launch it. While ComfyUI starts, the window shows the startup progress, then the ComfyUI interface once the server is ready.

Launching While Another Instance Is Running

When you launch a local instance while another local instance is running or starting, Comfy Desktop shows an An instance is already running dialog that lists the instances it would stop:

• Close & Launch: stops the listed instances, then launches the one you picked.
• Run All: launches the new instance alongside the running ones.

Dismiss the dialog to cancel the launch. Restarting an instance never shows this dialog. To stop seeing it, turn off Warn before running multiple instances in Desktop Settings → Preferences.

When the Port Is Already in Use

ComfyUI listens on port 8188 unless the instance passes --port. Before it starts ComfyUI, Comfy Desktop checks that port, and the instance’s If Port is Busy setting on the Startup Args tab decides what happens when something else already uses it:

• Use next available port (asks if --port is set), which is the default: Comfy Desktop starts ComfyUI on the next free port and says so in the startup progress. A busy port only stops the launch when the holder is a ComfyUI of this installation, see below.
• Ask what to do: the launch stops on Port already in use, which names what holds the port, and you choose the next step.

Setting --port in Startup Arguments also makes Comfy Desktop ask, even with the default setting, because that port was requested on purpose.

The message names what holds the port:

• Another Comfy Desktop instance: the message names that instance.
• A ComfyUI: the message says it looks like a ComfyUI instance, including one you started outside Comfy Desktop.
• Any other program: the message names the process, and Comfy Desktop does not offer to stop it.

The actions on that screen:

• Use next available port: launches this instance on the next free port instead.
• Stop process and retry: force-stops the process that holds the port, then launches again. It appears only when the holder looks like a ComfyUI, and the confirmation warns that unsaved work in that ComfyUI is lost.
• Return to Dashboard: cancels the launch.

If Comfy Desktop can tell that the holder is a ComfyUI of the same installation, for example one you started by hand in a terminal, it stops instead of offering another port, because a second copy would use the same database. Stop that copy, close the app that started it, or select Stop process and retry, then launch again. Comfy Desktop runs this check when the launch enables the asset system: it adds --enable-assets for ComfyUI 0.38.0 and later, unless the instance’s startup arguments pass --disable-assets.

A ComfyUI Left Behind by an Earlier Session

Before the port check, Comfy Desktop looks for a ComfyUI of the same installation that an earlier Comfy Desktop session left running. That process still holds the installation’s database, so a new ComfyUI would fail to start.

• Still working on a prompt: the launch stops and says so. Stop it and launch stops that ComfyUI and cancels the prompts it is working on. Letting it keep running cancels this launch.
• Processes that no longer answer on the port: the message names their PIDs and offers Stop them and launch.
• A process that will not exit: the message asks you to end it manually, then launch again.

Stopping an Instance

Select Stop from the instance card’s ⋮ menu. The ComfyUI server stops and the window stays open with a ComfyUI is stopped card. Select Relaunch ComfyUI to start the server again, or Return to Dashboard to go back to the Chooser.

Restarting After a Crash

If ComfyUI fails to start or exits unexpectedly, the window stays open with a card describing what happened:

• ComfyUI could not start: the instance did not start.
• ComfyUI exited unexpectedly: the process stopped. When Comfy Desktop can read it, the card also shows the exit code, or the signal that ended the process.

On Windows, a crash can report a memory access violation and note that some Microsoft Visual C++ Redistributable files appear to be missing. Expand the card’s logs for details, then select Restart ComfyUI to launch again, or Back to return to the dashboard.

If ComfyUI stops because it cannot open the asset database it keeps inside the installation, the error it stops with explains the reason instead of only reporting an exit code:

• Another ComfyUI is using this installation’s database: close that ComfyUI (or the app that started it), or give one of them its own database location with the --database-url startup argument.
• Any other database failure, from one locked by another program to one written by a newer version of ComfyUI or impossible to create in that folder: the message names the file and the fix, and ends with the option to start the instance without the asset system, by adding --disable-assets to its startup arguments.

Uninstalling an Instance

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When you want to remove an instance, two actions decide whether its files stay on disk.

1. Forget: Removes the instance from the app without deleting anything. The installation folder and all its data stay on disk. Use this when you only want to clean up the list but might need the instance again later.
2. Uninstall: Permanently removes the installation and all its files from disk. Model files in shared directories are not affected.

Uninstall is also on the instance card’s ⋮ menu. Forget is not part of that menu; you find it in the Manage panel, in the More menu at the bottom of the panel. An installation Comfy Desktop adopted, such as one migrated from Legacy Desktop, has no Forget action.

Duplicating an Instance

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You can duplicate an existing standalone installation. Open the card’s ⋮ menu and select Duplicate Instance, or use Duplicate Instance in the Manage panel’s More menu. The copy gets:

• A new Python environment
• The same ComfyUI version
• Its own custom node setup

Enter a name for the duplicate when prompted. The copy is created next to the original. Cloud, remote, and tracked installations cannot be duplicated.

Editing an Instance

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In the Manage panel for an instance, you can:

• Change the installation path
• Adjust launch arguments
• Modify model directories
• Update environment variables
• Rename the instance, from the name at the top of the About tab or from Rename in the More menu
• Change the connection address of a Remote Connection, in the About tab

Open the Manage panel by right-clicking the instance card (or selecting Manage in its ⋮ menu).

Error State

If an installation encounters a problem, an Error badge appears on its card. Select the badge to read the details: the message, the exit code or signal when Comfy Desktop has one, and the last lines of error output. Launching or restarting the instance clears the badge. If the problem comes back, check the logs at the Data Locations.