What is a 405 Method Not Allowed Error and How To Fix It

A particularly challenging status code that often causes confusion is the 405 "Method Not Allowed" error. Similar to other 400 errors, this error code, also known as "HTTP 405" or "405 error code," can interrupt access to your site, break functionality, and negatively impact the overall user experience, making it essential to address promptly.

To help you troubleshoot and fix 405 errors on your website, we’ll dive deeper into what this error means, explore the underlying causes, and outline actionable steps to resolve it.

What is a 405 error?

The 405 Method Not Allowed error is a client-side error that occurs anytime a user (also known as the client) sends a request using an HTTP method that is not supported by the server or endpoint for the resource they're requesting. In most cases, it means that there is a mismatch between the method the client used and the server’s capabilities or permissions.

HTTP request methods are used to define the exact actions that a client wants to perform, and they include methods/actions like:

• GET: Used to retrieve data from a server.

• POST: Used to submit data to a server.

• PUT: Used to update a resource.

• DELETE: Used to remove a resource.

However, not every server or endpoint supports all of these request methods. Sometimes it's for a good reason. You wouldn't want to allow users to remove pages from your website using the DELETE request, for example. Other times, though, 405 errors indicate an issue that needs to be fixed.

Common causes

There is a wide range of issues that can trigger a 405 Method Not Supported error. Some of the most common ones include:

• Incorrect or unsupported HTTP methods.

• Misconfigured web server settings or software.

• Issues with application routing or endpoint configurations.

• Incorrect .htaccess file directives.

• Problems with permissions or authentication.

• Use of outdated or incompatible plugins (WordPress or other CMS).

• API-specific issues (like incorrect HTTP methods in REST APIs).

• DNS misconfigurations or caching issues.

Understanding the potential causes of this error is the first step in diagnosing and resolving it. By identifying the root issue, whether it’s related to server configurations, application-level settings, or external factors, you can implement targeted fixes to restore functionality to your website.

Troubleshooting and fixing 405 errors

Due to the wide range of potential causes behind a 405 error, resolving it often requires a systematic, multi-step troubleshooting approach. If you encounter a 405 error message while trying to access a resource on your site (or you have users who are encountering this error), here are the troubleshooting steps you should take:

1. Check the HTTP request method

Start by confirming that the requested resource supports the HTTP request method being used. You can do this by reviewing the server or application documentation to see which methods are allowed. You can also use your browser developer console or an API testing tool to check if the request is valid.

2. Inspect server-side logs

Analyzing server logs such as error.log can often tell you a lot about the root causes of different errors, including 405 errors. Server-side tools like cPanel are helpful for accessing server logs and identifying configuration issues.

3. Verify server configurations

Double-check the web server software settings to ensure they align with the intended functionality of your website. For servers running software like Nginx or Apache, this involves reviewing configuration files such as nginx.conf, .htaccess, or other relevant server files. Look for routing rules, method restrictions, or directives that may block certain HTTP methods. If issues are found, update the configurations to explicitly allow the required HTTP methods for the resource in question.

4. Test application code

Discrepancies between the application code for handling HTTP requests and the server configuration can often cause 405 errors. Use debugging tools to verify that the application correctly handles required methods, and ensure compatibility with the server’s routing rules. If inconsistencies or restrictions are identified, adjust the code to support the appropriate methods and test thoroughly to confirm the error is resolved.

5. Update or deactivate plugins

If your website has plugins installed, one or more of them could be causing the 405 error by restricting certain HTTP methods. Before making any changes, back up your website to prevent potential disruptions. Next, ensure that all plugins are up to date, as outdated plugins may introduce compatibility issues. If updating doesn’t resolve the error, carefully deactivate all plugins and then reactivate them one at a time, testing your site after each activation to pinpoint the culprit.

6. Clear cache and cookies

Sometimes, cached data can cause a 405 error to persist even after fixes are implemented. Clearing your browser cache will eliminate this cached data and ensure that the most recent server configuration is being used. If your website uses a Content Delivery Network (CDN), you'll want to clear the CDN cache as well.

7. Check permissions and authentication

If the 405 error persists, check the file permissions for the resource you are trying to access and make sure they are correct. For restricted resources and actions, you'll also need to check that the authentication requirements are correctly configured.

8. Make DNS and domain checks

DNS misconfigurations can sometimes lead to 405 errors. Start by confirming that all DNS records are accurate and up-to-date. Next, look for any potential domain misconfigurations that might be affecting how requests are routed.

When to contact your hosting provider

If all else fails and you are unable to identify the cause of a persistent 405 error, you should contact your hosting provider for further support. You also may need to contact your hosting provider even if you are able to pinpoint what's causing the error if fixing it requires advanced server-side configuration or if you discover that the error is being caused by malware or other security issues.

Best practices

It's important to know how to fix 405 errors, but taking proactive steps to prevent them is even more valuable. Here are some best practices you can follow to prevent both 405 errors and a range of other errors on your site:

• Perform regular website backups so that you can quickly restore your site if issues occur.

• Test updates in a staging environment before applying them live.

• Configure servers to accept only necessary HTTP methods for resources.

• Keep plugins updated and test them individually when troubleshooting.

• Verify DNS and domain settings to ensure correct routing of requests.

• Enable server logging to monitor and resolve errors effectively.

• Use Web Application Firewalls (WAFs) and regularly update security protocols.

• Audit and manage configuration files (e.g., .htaccess) to prevent errors.

Maintain your website with SiteLock

405 errors can be a big problem when they prevent you or your users from accessing important resources on your website. And, in some cases, 405 errors can indicate even bigger problems, such as outdated files and plugins that could be major security vulnerabilities.

At SiteLock, we offer a range of advanced website security services and solutions to help website owners keep their sites error-free, functional, and secure. To learn more, check out how SiteLock works and contact us if you’d like further information before getting started.

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