How to Fix HTTP 505 Version Not Supported Error? [SOLVED]

What is HTTP 505 Version Not Supported?

The HTTP 505 error, known as “HTTP Version Not Supported,” occurs when the web server cannot handle the request or the server doesn’t recognize the HTTP protocol version from the client’s browser.

Typically, the HTTP 505 error occurs when the web server encounters a request with an HTTP version higher than it can handle.

Here are the common causes:

  • Outdated Web Server:

The web server might be using an old version of HTTP for instance (Apache or Nginx). Regular updates are essential to avoid this issue.

  • Client-Side Browsers:

Older browsers (like Internet Explorer) may attempt to connect to modern web servers using outdated HTTP versions.
You can switch to a modern browser like Firefox or Google Chrome.

How to Fix HTTP 505 Version Not Supported?

Now, let’s explore various ways to resolve the HTTP 505 Version Not Supported error:

1. Update Your Browser

If you’re using an outdated browser (such as Microsoft’s Internet Explorer), consider updating it to the latest version.
Modern browsers like Firefox or Google Chrome are better equipped to handle current web server protocols.

2. Utilize an alternative browser

If you consistently encounter the HTTP 505 error in a specific browser, consider switching to a different one. This approach helps identify whether the issue originates from the browser itself or if it’s related to server-side compatibility.

3. Clear Your Browser Cache

Browsers cache website features to improve speed and reduce network traffic.
Sometimes, cached content doesn’t match the actual website, leading to errors like 505.
Clear your browser’s cache to ensure smoother communication with web servers.

If you use Google Chrome, here’s how to clear its cache:

  1. Click the three dots in the top-right corner of your window. You can also use the keyboard shortcut (Ctrl + H).
  2. Go to History History.
  3. Click on Clear Browsing Data.
Clear browsing data
  1. A new window will appear. Choose the Time range, if you wish to erase all data, select All Time.
Choose the Time range
  1. Select what you’d like to clear- this could be browsing history, cookies, and other site data, or cached images and files.
  2. Then, hit the Clear Data button.

4. Verify the server’s compatibility with your browser’s HTTP version

While HTTP/1.1 is the most commonly supported version, newer servers may also accommodate HTTP/2 or HTTP/3.

If you’re using an older browser, consider updating it to a newer version that aligns with the server’s supported HTTP version.


When you encounter a 505 HTTP Version Not Supported status code error, it indicates that the server does not support the HTTP protocol version used in the request.

By executing all the solutions provided above, you can confidently address and resolve this error.

I hope this article helps you rectify this error.

For further learning, you can also check the following HTTP status code:

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