If your WordPress site is showing the 401 error code to other visitors, it’s important to fix the problem so that your visitors can enjoy your site. And if you’re experiencing the 401 error code when you visit someone else’s site, you’ll want to understand the problem so you know what’s happening.

What does the 401 error code mean?

A 401 Unauthorized error is an HTTP status code indicating that the server received an unauthenticated request. 401 error code responses are most often generated because of invalid credentials for a particular page or destination on your website. This status is typically sent with a WWW-authenticate header that contains information on how to authorize properly.

In human terms, this basically means that your client (e.g. your web browser) isn’t able to authenticate itself with the server and, as such, cannot view the resource. For example, a specific page might require a valid username and password to view.

The 401 error code, like other error codes in the 400-range, means there’s a problem on the client-side – AKA the problem lies on your web browser’s side (or another client), rather than the website you’re trying to visit.

401 error vs 403 error

People often confuse a 401 error with a 403, but the two are different. A 403 error means access to the page is forbidden, whereas a 401 error just means there’s a problem with authenticating access to the page. That is, a 401 means access is not necessarily forbidden, the server just cannot authenticate the request to grant access.

401 error code variations

The exact message that indicates a 401 error code varies depending on the server, but here are the typical 401 error code variations that you’ll see:

• 401 Unauthorized
• Authorization Required
• Access Denied
• HTTP Error 401 Unauthorized

What causes the 401 error code?

Here are some common causes of the 401 error code:

• Incorrect URL – sometimes the 401 error code is because of the wrong URL. Make sure that the URL for the site you want to access has been entered correctly.
• Invalid login credentials – some pages of a website require you to login in order to access the information. If you’re not logged in, you will very likely get a 401-error. Make sure that the login credentials you are entering are accurate.
• False login requirement – this occurs rarely but, in some cases, a website that should not require a login will still show a login page. This indicates an issue on the admin side and will often throw up a 401-error.
• DNS errors – occasionally, domain name system failures may result in a 401 response. DNS malfunctioning is less common.
• Security/firewall issues – some WordPress security plugins or firewalls can cause a 401 error if they detect malicious activity.
• Plugin issues – a WordPress plugin on your site might be triggering the 401 error code.

How to fix the 401 error code on WordPress

Often, 401-error codes can be fixed by simply hitting the refresh button. If refreshing your page doesn’t work, try the following fixes:

1. Check the URL for errors

It is possible that a 401 error occurs because you have typed the URL incorrectly or the login URL has been changed. Alternatively, you may have clicked on an outdated link in your web browser. In cases where a page no longer exists, the server might show a 401 code. Check the URL for spelling mistakes. You can also use a search engine to find the correct URL of the webpage you are trying to access.

2. Clear browser cache and cookies

Your browser’s cache helps improve your overall surfing experience by decreasing the loading time of websites. To do this, browsers store local copies of the content you visit most frequently. Your browser’s cache can sometimes overlap with the live version of your application, resulting in a 404 error code.

To fix this error, just clear the browser’s cache.

Similar to the cache, there are HTTP cookies which are basically tiny pieces of stored data. Invalid and/or corrupted cookies can cause an authentication error. Clear the cookies and try to open the page again.

3. Deactivate your WordPress plugins

Because WordPress plugins can alter how your site functions, they’re a typical cause of the 401 error code on WordPress.

In the case of WordPress security plugins, sometimes the plugin intends to do this. For example, some plugins will lock down your login page if the plugin thinks you’re under attack, which can trigger the 401 error code when you try to open your login page. Or the firewall in a plugin like Wordfence might cause the issue.

In this case, once you figure out the issue by deactivating the plugin, you can reach out to the plugin’s support to understand the issue.

Other times, it could be an unintended compatibility issue.

To figure out which plugin is causing the 401 error, try deactivating all of the plugins at your site and reactivating them one-by-one. Or, if the error only appeared after you installed a new plugin, try deactivating that plugin first.

4. Remove server-level password protection

If you’re using htaccess/htpasswd to protect parts of your WordPress site with an extra username/password, try deactivating this extra password protection.

Many web hosts also give you a tool to control such passwords from cPanel. Look for a tool named something like:

• Password protect directories
• Directory privacy

5. Flush your DNS

In rare cases, DNS errors can cause the server to show a 401-error code on your browser. To fix this, you need to flush your DNS. Although this is a fairly unusual cause, it is quite simple to repair.

For Windows users:

• Log in to your computer as an administrator
• Open a “search” window
• Type in CMD.exe in the search field to open Command Prompt
• Enter this little code in the CMD interface: “ipconfig/flushdns”

For macOS users:

• Open the Command Terminal
• Enter this code in terminal interface: “sudo killall -HUP mDNSResponder”

6. Try waiting

Like security plugins, some WordPress hosting companies will temporarily block your IP if they think you’re doing something malicious – e.g. entering the wrong password. In this case, you can try waiting to see if that fixes the issue, as sometimes your site is only locked down for a short period of time.

Additionally, many WordPress websites need regular downtime for maintenance. If you’re seeing a 401-error on someone else’s site, there may be maintenance or construction going on at the backend causing temporary login issues. Try giving the admins some time and logging in a few minutes later.

Conclusion