While surfing the internet, you may have come across any of these error messages- 400 Bad Request, Bad Request – Invalid URL, or HTTP Error 400 – Bad Request. This is a typical client error that many internet users face on a daily basis. Generally, when you search something on your web browser, your web browser (client) and the server starts to communicate to give you a result.

But if there are some problems on behalf of the client (web browser), then the server sends a cryptic error message. It can be a bit tricky to solve this error on your own. So, we are going to show you some solutions that will help you with this error.

What causes the HTTP Error 400?

When a client or a web browser makes a request, the server sends an HTTP code. But if the server interprets the request as harmful, it will prevent the website from being fully displayed, and it will send the HTTP Error 400. In most cases, your browser is the reason behind this error, but there are some other possible reasons for this error too. Here’s a list of all the reasons for the HTTP Error 400.

  • Wrong URL: If you mistype the URL in the address bar, then you will face the HTTP Error 400. This is otherwise known as invalid syntax.
  • DNS Record is outdated: If your DNS cache contains data related to some incorrect IP addresses, then that will help in creating the error.
  • Large Files: The server qualifies the large files as Bad Request. So, if you upload large files, you will get the 400 Bad Request error.
  • Cookies: No matter what browser you use, if your browser has incorrect or outdated cookies, you will receive the error.

Solutions to Fix HTTP Error 400?

Sometimes the 400 Bad Request error is temporary. So, before moving forward to the complex solutions, we will advise you to refresh the web page. If refreshing your page resolves the error, then you don’t have to go through the solutions. You can also choose to change your browser as, in most cases, the present browser is at fault for the error. If these two basic steps don’t work out, go through the solutions given below.

Note: These solutions will need some modifications to your site or app. So, you should backup all your essential data.

Solution 1: Clear cookies from your browser

As we have mentioned earlier, invalid or outdated cookies tend to produce the 400 Bad Request error. So, the first step should be to clear cookies from the browser you use.

To clear cookies from Google Chrome, follow these steps.

  • Go to Chrome and click on the More (three dots) option.
  • Then, choose the More tools option.
  • Click on the “Clear browsing data” option.
  • Besides Time range, select “All time.”
  • Check both the boxes beside Cookies and other site data and Cached images and files options.
  • Select “Clear data” to delete everything.

To clear cookies from Firefox, follow these steps.

  • Go to Menu.

  • Choose Options and then go to the Privacy & Security option.

  • Click on Cookies and Site Data.

  • Select the Manage Data option.

  • Type the name of the website which cookies you want to clear in the Search websites field.

  • Choose Remove, all shown to remove all cookies and storage data.

  • If you want to remove selected items, choose the Remove selected option.

  • Select “Save changes.”

  • Then, click Remove in the Removing cookies and site data confirmation box.

  • Go to the Menu and open the Library.

  • Choose History and then select the Clear Recent History option.

  • In the Time range option, set to clear everything.

  • Besides Details, click on the arrow to expand the list.

  • Choose Cookies.

  • Now, select “Clear Now” and exit.

To clear cookies from Microsoft Edge, follow these steps.

  • Go to Microsoft Edge and click on “Hub.”
  • Click on “History“
  • Then, choose the “Clear all history” option.
  • Then, select everything that you want to remove and choose “Clear.” If you use Cortana and want to clear the browsing history, then click on Change what Microsoft Edge knows about me in the cloud.
  • Next, choose Clear browsing history.

Solution 2: Fix the incorrect URL

An incorrect URL means you have typed the wrong URL address, or you have inserted special characters that aren’t allowed. It’s a common cause for creating the 400 Bad Request Error. You should check the spellings, special characters, path, query, or fragment portions after the domain name. If you find everything is alright with the URL, then go to the next solution.

Solution 3: Fix large file issue

If you upload large files, then you will encounter the 400 Bad Request error. Large files include uploads that don’t belong to your computer. In simple words, the files sent to other computers that are deemed uploads from the server in your web browser or web app. To fix this issue, upload smaller files. If uploading smaller files doesn’t work, then go to the next solution.

Solution 4: Fix incorrect DNS

While browsing the internet, the domain names translate into IP addresses. To simplify the whole process, your computer stores the data in the DNS cache. Due to this, when the next time the same domain is entered into the browser, name resolution takes place directly from the DNS cache. But if the DNS cache is incorrect or corrupted, then the HTTP error 400 will appear. To fix this issue, you have to run the following command line in the Command Prompt window of your Windows computer.

ipconfig /flushdns

If deleting the DNS cache didn’t solve the error, follow the next solution.

Solution 5: Try changing the common software packages on the server

If you have done some recent changes to the software or content management systems, it can produce the HTTP Error 400. To fix this issue, follow these steps given below.

  • Revert the updates of the recently updated softwares to a previous version before the error started appearing.
  • Revert the recently updated extensions or modules.
  • Uninstall any newly installed extensions, modules, or plugins.
  • Verify database, thereafter go through the records modified by extensions or plugins.

Solution 6: Check your Server

To check the server, follow these steps.

  • Look for invalid HTTP headers.
  • Go through the server-side logs of your web browser’s requested pages, connected servers, database results.
  • Manually debug the browser application code or script. Make a copy of the browser application to a local development machine before you perform a debug process. Do this to recreate the exact situation before the 400 Bad Request error happened.

Solution 7: Reset your present browser

This process will reset your default search engine back to Google, all the homepage and tabs, the new tab page, and pinned tabs. It will also reset the content settings, cookies and site data, extensions, themes, and all the devices you’re signed into. Follow these steps to reset the Chrome browser.

  • Go to Chrome and click on the three dots (More) icon.
  • Choose Settings from the drop-down menu.
  • Choose the “Advanced” option.
  • Go to the Reset section and choose “Reset.”
  • You have to confirm the resetting procedure of the Chrome browser by clicking Reset.

HTTP Error 400 is a client-based error, which means the client (web browser) is mostly at fault. So, the error is needed to be solved on the client’s part. To help you with resolving this error, we have provided you with the best solutions.

They are easy and can be performed manually. Go through the solutions to see which one works for you. We hope you become successful in resolving the error and enjoy surfing the internet again. If you have any queries or feedback, please write down the comment in the below comment box.