Web Browsers - How to Fix a "Bad Request" Error

This document describes what to do if you receive a 400 Bad Request error message upon loading a website.

Problem

When you attempt to access a website, you may sometimes instead receive a "Bad Request" error message where the website content should have loaded. This error often contains the number "400" and may include additional text, such as "Your browser sent a request that this server could not understand. Size of a request header field exceeds server limit."

Solution

First, check the website URL you entered to make sure it is correct. If the web address appears to be entered correctly, then the issue can usually be resolved by clearing your browser's cache and cookies.

Note: Windows users can use CTRL + F5 to bypass the cache and download a website's complete content.

For instructions on performing these steps, click on the appropriate link for the web browser you are using:

Desktop Web Browsers

Clearing the browser cache prevents you from using old/out-of-date versions of websites and protects your personal information. It also helps running some applications better on your computer by freeing up space.

Note: Make sure you set the Time Range to the "All Time" or "Everything" options when available to clear all data. Please save any unpublished work before proceeding; you will be logged out of all sites and applications and will need to re-authenticate.

Table with browser name and links to Windows documents and macOS documents.
Browser Windows Document Link macOS Document Link
Google Chrome
Google Chrome
Chrome (Win) - Clearing Cache and Cookies Chrome (Mac) - Clearing Cache and Cookies
Firefox
Firefox
Firefox 57+ (Win) - Clearing Cache and Cookies Firefox 21+ (Mac) - Clearing Cache and Cookies
Safari
Safari
Safari (Win) - Clearing Cache and Cookies Safari 10.0.1+ (Mac) - Clearing Cache and Cookies
Microsoft Edge
Microsoft Edge
Edge (Win) - Clearing Cache and Cookies None
Opera
Opera
Opera (Win) - Clearing Cache and Cookies Opera 28.0 (Mac) - Clearing Cache and Cookies
New Microsoft Edge logo
New Microsoft Edge
New Edge (Win 10, 8, 7, MacOS) - Clearing Cache and Cookies New Edge (Win 10, 8, 7, MacOS) - Clearing Cache and Cookies

Mobile Web Browsers

Table with mobile Operating System and corresponding documents on clearing cache and cookies.
Operating System Document Link
Android Icon
Android
Android (Jellybean) - Clearing Cache and Cookies on Google Chrome
iOS Icon
iOS
iOS - Clearing Cache and Cookies
webOS Icon
webOS
HP webOS 2.x - Clearing Cache and Cookies
Windows Phone Icon
Windows Phone
Internet Explorer (Windows Phone) - Clearing Cache and Cookies

Legacy Versions

Windows

Table with browser name and links to Windows documents.
Browser Document Link
Internet Explorer 9, 10, & 11
Internet Explorer 9, 10, & 11
Internet Explorer 9, 10, and 11 (Win) - Clearing Cache and Cookies
Internet Explorer 6
Internet Explorer 6
Internet Explorer 6 (Win) - Clearing Cache and Cookies
Internet Explorer 7
Internet Explorer 7
Internet Explorer 7 (Win) - Clearing Cache and Cookies
Internet Explorer 8
Internet Explorer 8
Internet Explorer 8 (Win) - Clearing Cache and Cookies
Firefox 3.5
Firefox 3.5
Firefox 3.5 (Win) - Clearing Cache and Cookies


Keywordsmozilla firefox ff internet explorer ie google chrome safari website http "400 bad request" "Your browser sent a request that this server could not understand." "Size of a request header field exceeds server limit." cookies cache "404 bad request" query /n 400 youtube   Doc ID47897
OwnerHelp Desk KB TeamGroupDoIT Help Desk
Created2015-03-02 17:45:32Updated2024-04-16 16:43:53
SitesDoIT Help Desk
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