In a previous post we presented the most common HTTP error codes and status codes<\/a>, but this post, we’ll explain what the 401 error is<\/a>, what causes it<\/a>, and how to fix<\/a> the error 401 message.<\/p>\n<\/div>\n\n\n\n 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.<\/p>\n\n\n\n In human terms, this basically means that your client (e.g. your web browser<\/em>) 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.<\/p>\n\n\n\n The 401 error code, like other error codes in the 400-range, means there’s a problem on the client-<\/em>side – AKA the problem lies on your web browser’s side (or another client), rather than the website you’re trying to visit.<\/p>\n\n\n\n People often confuse a 401 error with a 403, but the two are different. A 403 error means access to the page is forbidden<\/em><\/a>, 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.<\/p>\n\n\n 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:<\/p>\n\n\n\n Here are some common causes of the 401 error code:<\/p>\n\n\n\n Often, 401-error codes can be fixed by simply hitting the refresh button. If refreshing your page doesn\u2019t work, try the following fixes:<\/p>\n\n\n\n It is possible that a 401 error occurs because you have typed the URL incorrectly or the login URL has been changed<\/a>. 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.<\/p>\n\n\n Your browser\u2019s 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\u2019s cache can sometimes overlap with the live version of your application, resulting in a 404 error code.<\/p>\n\n\n\n To fix this error, just clear the browser\u2019s cache.<\/p>\n\n\n\n Similar to the cache, there are HTTP cookies<\/a> 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.<\/p>\n\n\n Because WordPress plugins can alter how your site functions, they’re a typical cause of the 401 error code on WordPress.<\/p>\n\n\n\n In the case of WordPress security plugins<\/a>, 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<\/a> might cause the issue.<\/p>\n\n\n\n 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.<\/p>\n\n\n\n Other times, it could be an unintended compatibility issue.<\/p>\n\n\n\n To figure out which plugin is causing the 401 error, try deactivating all of the plugins on 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.<\/p>\n\n\n If you’re using htaccess\/htpasswd to protect parts of your WordPress site with an extra username\/password, try deactivating this extra password protection<\/a>.<\/p>\n\n\n\n Many web hosts also give you a tool to control such passwords from cPanel<\/a>. Look for a tool named something like:<\/p>\n\n\n\n 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.<\/p>\n\n\n\n \ud83d\udc49 For Windows users<\/strong>:<\/p>\n\n\n\n \ud83d\udc49 For macOS users<\/strong>:<\/p>\n\n\n\n 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.<\/p>\n\n\n\n Additionally, many WordPress websites need regular downtime for maintenance. If you\u2019re 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.<\/p>\n\n\n At this point you should have a solid understanding of the general definition of the 401 error code. However, sometimes people ask about it in different contexts or simply want some quick answers to some quick questions. Below you’ll find responses to three of the most commonly asked questions regarding this http error code.<\/p>\n\n\n\n In the context of REST API<\/a>, the 401 status code means “Unauthorized.” It’s used when the server requires user authentication for the requested resource. If you receive a 401 response, it indicates that you either haven’t provided valid credentials or haven’t provided any credentials at all. The server may include a “WWW-Authenticate” header in the response to guide you on how to authenticate yourself, such as including an API key or valid username and password.<\/p>\n<\/div><\/details>\n\n\n\n An example of a 401 error is when you try to access a restricted page on a website without logging in or providing the correct credentials. It’s like attempting to enter a restricted area without the right key or permission. The server will respond with a 401 error, indicating that you need valid login credentials to access the requested content.<\/p>\n<\/div><\/details>\n\n\n\n The message “401 Unauthorized: Access is denied due to invalid credentials” indicates that the server received a request that requires authentication, but the credentials provided by the client are either missing or incorrect.<\/p>\n\n\n\n In simpler terms, when you encounter this error, it means that you’re trying to access a resource or perform an action that requires you to provide valid login credentials (such as a username and password), but the ones you provided are not recognized or are missing altogether. As a result, the server denies access to the requested content or functionality.<\/p>\n<\/div><\/details>\n<\/div>\n\n\n A 401 error indicates a client-side problem with authentication. That is, your web browser is having issues authenticating itself with your WordPress site’s server.<\/p>\n<\/div>\n\n\n\n Before you start digging into any in-depth troubleshooting, try a few quick fixes first. Make sure that the URL you\u2019re using is correct, and don\u2019t forget to clear your browser\u2019s cache and cookies.<\/p>\n\n\n\n Also consider any security tools you may be using on your site, as well as any server-level passwords you might have added, like a password via htaccess<\/a> and htpasswd. You can also try deactivating your plugins.<\/p>\n\n\n\n Do you have any questions about the 401 error code? Let us know in the comments!<\/em><\/strong><\/p>\n\n\nWhat does the 401 error code mean? \ud83e\udd14<\/h2>\n\n\n
![\"401](\"https:\/\/mllj2j8xvfl0.i.optimole.com\/cb:c5QE.37290\/w:auto\/h:auto\/q:mauto\/f:best\/https:\/\/themeisle.com\/blog\/wp-content\/uploads\/2025\/09\/401-error.png\")
<\/figure><\/div>\n\n\n401 error vs 403 error<\/h3>\n\n\n\n
401 error code variations<\/h3>\n\n\n\n
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What causes the 401 error code? \u26a0\ufe0f<\/h2>\n\n\n\n
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How to fix the 401 error code on WordPress \ud83d\udd27<\/h2>\n\n\n\n
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1. Check the URL for errors<\/h3>\n\n\n\n
2. Clear browser cache and cookies<\/h3>\n\n\n\n
3. Deactivate your WordPress plugins<\/h3>\n\n\n\n
4. Remove server-level password protection<\/h3>\n\n\n\n
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5. Flush your DNS<\/h3>\n\n\n\n
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6. Try waiting<\/h3>\n\n\n\n
401 error code FAQ \ud83d\ude4b<\/h2>\n\n\n\n
Conclusion \ud83e\uddd0<\/h2>\n\n\n\n