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HTTP 400 Errors - Causes and Solutions

HTTP 400 Errors – Causes and Solutions

404 bad request errorSurfing on the Internet, it’s common to meet some HTTP errors, such as 404 Not Found, 500 Internal Server Error, and 400 Bad Request. As we have explained the former two errors in detail, today, we are going to discuss HTTP 400 Error.

HTTP 400 Error is a bad request error message that indicates the request cannot be replied because of the bad syntax. Usually, people meet this problem when the browser sends or receives a message with wrong formatted. And also, it appears in many other reasons like faulty RAM, wrong plugins, malware applications, etc.

As a common error, people may encounter it in many cases and due to various reasons. In order to help readers solve this problem easily, in the below content, we just carefully introduce the causes and come with several possible solutions.

About HTTP 400 Error

HTTP 400 Error displays inside a browser window when it sends an incorrect message that the server cannot understand or process it. It is customizable, sometimes be presented as “400 Bad Request Error”, “Error 400 Bad Request”, “HTTP Error 400 – Bad Request”, “400: Bad Request”,ect, depending on the webmasters’ design.

HTTP 400 Error showcase

There are many cases that many result in this error, such as

  • Damaged Windows registry
  • Bad RAM memory
  • Virus
  • Malware & spyware
  • Corrupt DLL file
  • Incorrect security settings

For different causes, you need to come out a different solution for the problem. In the below, we come out some resolutions to help you resolve this problem efficiently.

How to Fix HTTP 400 Error?

  1. Check for the URL link again.
  2. A fault URL is the most general reason for a 400 error. Once you type a wrong URL or click on a link with some other mistake, it may bring you with a 404 error message. At this moment, you need to be calm and carefully check for the link in the address bar, keeping it is the same with your target link. And then, you can press F5 or the refresh button on the browser to resend your request.

  3. Clear All Your Cookies.
  4. 400 error happens because of the corrupted cookie files. It’s hard to judge which file is damaged. The easiest and fastest way is to clear all cookies on your browser. We guide you handle it in Chrome browser.

    Click on options on the upper right corner and then select Settings.


    It takes you to configure the browser settings, such as login, appearance, users, etc. Search for “cookies” in the search box and it presents you the below content. Click on Content settings and check all options below.

    content settings

    Click on the button of All cookies and site data.

    All cookies and site data

    Then, you can choose a specific cookie to delete or just simply delete all cookies. After done all operations, you can type your URL or visit the link again and check whether the problem is solved.

    delete cookies

  5. Fix the Error with a Registry Cleaner.
  6. The 400 Bad Request Error is generally caused by corrupt registry keys and less maintenance for your computer. If the 400 error come on due to the damaged Windows registry, you can manually repair the registry entries one by one by hand. However, to save you much time, we suggest you to download and install a registry cleaner to eliminate the problem. There are many popular tools helping you simplify the work, such as Wise Registry Cleaner, CCleaner, Comodo System Utilities, and more.

  7. Contact the Webmaster.
  8. Sometimes, the 400 Bad Request Error comes with the server issues. For this reason, you are unable to access to the webpage with your own effort. It’s a time to contact the webmaster or just switch to another site. To contact the site owners and notify them the error message, you can send email via webmaster@sitedomain.com. Note to replace the sitedomain.com with your focused site domain.


Joyce is a professional writer & SEOer who loves trying new things and sharing the experience through blogging. She loves clean design, playing with different WordPress themes, SEO, etc. Now she is very struggle with purchasing a bubbling apartment in downtown. You can help her by clicking our ADs or making a purchase via our links ;-)


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