YouTube error 400: Your client issued a malformed or illegal request [FIX]

Vlad Turiceanu
by Vlad Turiceanu
Affiliate Disclosure
Share this article:

  • Youtube is an extremely popular platform specialized in streaming the latest videos at high-quality.
  • In this article we're taking a look at fixing Error 400, a pesky issue many have encountered. 
  • Find out more about troubleshooting your favorite software tools by checking out our  Web App Hub
  • Enjoy your online streaming and learn how to fix common bugs by visiting our Youtube Section
Youtube errors
To fix various PC problems, we recommend DriverFix: This software will keep your drivers up and running, thus keeping you safe from common computer errors and hardware failure. Check all your drivers now in 3 easy steps:
  1. Download DriverFix (verified download file).
  2. Click Start Scan to find all problematic drivers.
  3. Click Update Drivers to get new versions and avoid system malfunctionings.
  • DriverFix has been downloaded by 0 readers this month.

YouTube is the most popular video sharing site in the world. It’s accessed by millions of users every day that upload and search all sorts of video content. Thus, we can say it’s one of the biggest search engines, too.

YouTube was created in 2005, and in October 2006 Google acquired it and transformed it in the giant that is today.

Even though the site is constantly being developed and improved, sometimes some unexpected errors can show up. That’s the case with the Error 400: your client has issued a malformed or illegal request and today we’ll take a look at it.

A lot of users reported the Error 400 in YouTube, and although is an old and known issue, the cause is still a a mystery to Google. Let’s find out how to fix it.

Fixing YouTube error 400: Your client has issued a malformed or illegal request, usually involves clearing all the cookies. The error is mainly caused by shared cookies between YouTube and other extensions. If this action doesn’t solve the problem, you need to clear the specific faulty cookies from Developer tools or use Incognito mode.

It seems that the error is caused by an extension called The Great Suspender. This extension shares the cookies with YouTube and sometimes alters them, leading to the appearance of the Error 400.

How to solve error 400 in YouTube?

1. Use Opera

Opera is one of the most popular browsers of the moment due to the fact that it’s a fast search engine with a built-in ad blocker and a free VPN that keeps your internet experience safe and productive.

One important aspect of the Opera platform is that it uses less processing capacity than any other browser, this way you are guaranteed to always enjoy smooth online surfing.

You’ll be delighted with the user-friendly interface that makes possible chatting and browsing at the same time thanks to the built-in messenger on the side-bar of the page.

Another fun characteristic is the customizing feature that allows you to choose from a variety of themes. You can keep your favorite sites one click away by bookmarking them and save loads of time.



Enjoy safe and fast online browsing sessions with a search engine built to to make your work-flow easy and fun!
Check priceVisit website

2. Clear the cookies from Chrome’s settings

  1. Open Chrome.
  2. Go to Settings, click Advanced, access Content settings.
  3. Click Cookies, then pick See all cookies and site data.
  4. Type youtube, in the search-bar from the top-right of the page
  5. All the cookies related to YouTube should appear. Click on Remove all shown or choose only the faulty ones called gsScrollPos-[4-digit number].

Alternatively, you can do the same process by opening a new tab in Chrome and by typing in the address bar: chrome://settings/siteData .

3. Clear cookies using Developer Tools

  1. Open Chrome, go to YouTube site.
  2. On your keyboard press Ctrl + Shift + I.
  3. In the Developer Tools click More and then Application.

4. In the left panel, under Storage, expand Cookies, all the cookies should appear.

5. Delete the gsScrollPos-[4-digit number] and the error should be gone.

4. Other general fixes

  1. Use Incognito Mode.
  2. Replace the direct link with the video id.
  3. Clear the full cache and cookies from Clear browsing data in Chrome.

4. Reinstall Chrome.

You can also try these easy and general fixes that proved to work for some users.

These solutions are relatively simple and you should have no problem solving Error 400: your client has issued a malformed or illegal request. Remember that The Great Suspender extension is the main cause, but it’s not the only one.

We’d like to know your thoughts on this subject so feel free to share them in the comments section below.

FAQ: Learn more about Youtube errors

  • What does your client has issued a malformed or illegal request mean?

This error is usually caused by a specific extension, but there also other aspects at the root of this problem, see the solutions in our guide about the YouTube error 400: Your client issued a malformed or illegal request.

  • How do I fix YouTube error 400?

Many users have also confronted with this problem in particular situations, and in our article we detail all fixes you can apply when YouTube TV error 400 appears on smart TVs.

  • Why do I keep getting YouTube errors?

Lately the most common issue that people encountered on their favorite streaming platform is a YouTube error message when trying to sign in, check out some easy fixes to this problem.

Was this page helpful?
Thanks for letting us know! You can also help us by leaving a review on MyWOT or Trustpillot.
Get the most from your tech with our daily tips
Tell us why!