How to fix Error response from daemon: plugin already exists in Docker

First, verify which plugins are currently installed on your system:

# List all installed plugins
docker plugin ls

# Get more details about a specific plugin
docker plugin inspect <plugin_name>

This confirms whether the plugin is actually installed and shows its current state (enabled/disabled). The output includes:
- Plugin name and tag
- Whether it's enabled
- Plugin description

Note: If the plugin shows as installed but you still want to reinstall it, proceed to the next steps.

Before you can remove a plugin, you must disable it first. Docker does not allow removal of enabled plugins:

# Disable the plugin
docker plugin disable <plugin_name>

# Example with a volume plugin
docker plugin disable vieux/sshfs

If the plugin is in use by containers or volumes, you'll need to use the force flag:

# Force disable (use with caution)
docker plugin disable -f <plugin_name>

Warning: Force-disabling a plugin that's actively in use may cause containers using it to fail. Stop dependent containers first when possible.

Once disabled, remove the plugin from your system:

# Remove the plugin
docker plugin rm <plugin_name>

# Example
docker plugin rm vieux/sshfs

If removal fails because the plugin is still referenced, you can force removal:

# Force removal
docker plugin rm -f <plugin_name>

Important: Even with -f, Docker will not remove an enabled plugin. You must disable it first.

After removal, verify it's gone:

docker plugin ls

Now you can install the plugin fresh:

# Install the plugin
docker plugin install <plugin_name>

# Install with auto-grant permissions (useful in scripts)
docker plugin install --grant-all-permissions <plugin_name>

# Example
docker plugin install vieux/sshfs

The --grant-all-permissions flag automatically accepts the plugin's permission requirements, which is useful for automation but should be used carefully in production.

After installation, verify the plugin is enabled:

docker plugin ls

If you want to update to a newer version while preserving plugin state, use upgrade instead of reinstall:

# Disable the plugin first
docker plugin disable <plugin_name>

# Upgrade to the latest version
docker plugin upgrade <plugin_name>

# Upgrade to a specific version
docker plugin upgrade <plugin_name>:<tag>

# Re-enable the plugin
docker plugin enable <plugin_name>

Note: The upgrade command preserves the plugin's configuration and any associated data (like volume driver data). This is safer than remove/reinstall when the plugin has state you want to keep.

For automation scripts where the plugin may or may not be installed, add a check before installation:

#!/bin/bash
PLUGIN_NAME="vieux/sshfs"

# Check if plugin exists
if docker plugin inspect "$PLUGIN_NAME" > /dev/null 2>&1; then
    echo "Plugin $PLUGIN_NAME already installed, skipping..."
else
    echo "Installing plugin $PLUGIN_NAME..."
    docker plugin install --grant-all-permissions "$PLUGIN_NAME"
fi

Or use a one-liner that handles both cases:

docker plugin inspect vieux/sshfs >/dev/null 2>&1 || docker plugin install --grant-all-permissions vieux/sshfs

This pattern makes your scripts idempotent - they can run multiple times without failing on the "already exists" error.