423 Locked

What HTTP 423 Locked Means

The resource being accessed is locked.

A WebDAV status indicating the target resource is locked and cannot be modified until the lock is released.

Common Causes

• WebDAV resource locked by another user or session
• A previous lock was not released
• Editing a file open elsewhere

How to Fix It (For Visitors)

• Wait for the other user to finish, then retry
• Close the file in other applications

How to Fix It (For Developers/Admins)

• Acquire or supply the correct lock token
• Release stale locks
• Surface lock ownership in the error response

Returning a 423 Locked (Code Examples)

If you build APIs or web apps, here is how to send an HTTP 423 response and how to test for it:

Node.js (Express)

app.get('/resource', (req, res) => {
  res.status(423).json({ error: 'Locked' });
});

Python (Flask)

@app.route('/resource')
def resource():
    return jsonify(error='Locked'), 423

PHP

<?php
http_response_code(423);
header('Content-Type: application/json');
echo json_encode(['error' => 'Locked']);

Check the status with curl

curl -I https://example.com/resource
# Look for: HTTP/1.1 423 Locked

Frequently Asked Questions

What does HTTP 423 Locked mean?

A WebDAV status indicating the target resource is locked and cannot be modified until the lock is released. In short: The resource being accessed is locked.

Is 423 Locked a client or server error?

423 is a 4xx client-error code, so the request itself needs to change. The server is running normally and is rejecting the request as it was sent by the browser, app, or API client.

How do I fix a 423 Locked error?

Acquire or supply the correct lock token. Release stale locks. Surface lock ownership in the error response.

Official Specification

The 423 Locked status code is defined in RFC 4918 Section 11.3.

View the IANA HTTP Status Code Registry →