Seeing the “505 HTTP Version Not Supported” error appear can be frustrating for website owners and users alike. This error indicates a mismatch between the HTTP protocol version supported by the client and server, preventing communication between them.
While upgrading the web server or application to support newer versions of HTTP is one solution, it may not always be feasible. In this post, we’ll explore what causes these 505 errors and some troubleshooting steps you can take to prevent or resolve them without needing large infrastructure changes.
Using techniques discussed below you can quickly get your site back up and running as it should be. Read on to learn how to tackle these cryptic 505 errors and restore normal website functionality for your visitors.
Understanding the ‘505 HTTP Version Not Supported Error
The ‘505 HTTP Version Not Supported’ status code is an HTTP error that indicates there is an incompatibility between the HTTP protocol version supported by the server and the version being used by the client.
When a user tries to access a website, the browser (client) makes a request to the server using the HTTP networking protocol. There are different versions of HTTP, like HTTP 1.0, 1.1, 2.0, etc. If the HTTP version utilized by the client is not supported by the server, the server will return a ‘505’ error code in the response.
This prevents further communication between the client and server, leading to the website being inaccessible to the user. In addition to creating a poor user experience, if visitors cannot access the site, ‘505 errors can also negatively impact search engine optimization rankings if search engine crawlers are unable to properly index some or all of the site’s pages.
Common Causes of the ‘505 HTTP Version Not Supported Error
To be able to prevent and quickly troubleshoot ‘505’ errors, you first need to understand the most common underlying causes:
Outdated Server Configuration
One of the most common triggers of ‘505’ errors is an outdated configuration on the web server. Server software like Apache or Nginx needs to be kept updated to support new versions of HTTP as they are introduced and adopted. Old, outdated server configurations often do not recognize newer HTTP protocol versions and respond with ‘505’ errors instead.
Browser Compatibility Issues
In some cases, the ‘505’ error may stem from the browser rather than the server. Browsers also need to be updated by the user to support new HTTP protocol versions. An outdated browser may only support older versions like HTTP 1.0 or 1.1, while the server is using a newer standard like HTTP 2 or 3.
SSL/TLS Certificate Problems
SSL/TLS certificates play an important role in enabling secure HTTPS connections between the client and server. However, certificate-related problems can also lead to ‘505’ errors in some situations.
Insufficient Server Resources
Hosting servers have finite resources including RAM, CPU cores, and network bandwidth. If your hosting resources are inadequate to handle current traffic loads, all sorts of unpredictable HTTP errors can start occurring, including ‘505’ issues.
Preventing ‘505 HTTP Version Not Supported’ Errors
Now that we’ve identified the common causes, let’s discuss proactive steps to prevent these errors from occurring in the first place.
Regularly Update Server Software
One of the most important prevention steps is to keep your web server software regularly updated. Server updates ensure compatibility with the latest HTTP standards and browser versions.
Set up automatic background updates if available. If not, schedule a monthly or quarterly maintenance window to manually update the server software to the current stable releases. Staying updated is one of the top ways to avoid ‘505’ errors.
Proactively Manage SSL/TLS Certificates
Meticulously manage your SSL/TLS certificates to avoid expiration or misconfiguration issues. Obtain certificates from trusted authorities to ensure broad browser acceptance.
Set calendar reminders for renewals to replace certificates before they expire. Double check proper server-side installation and integration to avoid handshake failures.
Test Browser Compatibility
Make browser compatibility testing a regular maintenance routine. Test your website across different browser versions on both desktop and mobile to uncover any version-related errors.
Encourage users to keep their browsers updated by prominently promoting the benefits of upgrading to the latest browser releases.
Upgrade Hosting Plan If Needed
Keep a close eye on server resource metrics, and watch for any indications of constrained bandwidth, CPU, memory, or storage. If your hosting plan becomes underpowered as your site grows, upgrade to more robust hosting tiers or switch providers.
Proactively upgrading your hosting can help avoid intermittent errors that might occur during traffic spikes on limited resources.
Troubleshooting ‘505 HTTP Version Not Supported’ Errors
Despite your best prevention efforts, 505 errors can still happen occasionally. The key is having an effective troubleshooting methodology to quickly identify and resolve any issues. Here are tips for troubleshooting these errors:
Review Server Logs
Your first step is to review the server’s error logs. The logs will contain details about the specific HTTP requests receiving ‘505’ responses. Look for any mentions of unsupported HTTP versions to identify the source of the conflict.
Logs may also indicate certificate problems, lack of server resources, or other contributing factors. Use log data to unravel where the incompatibility lies.
Double Check SSL/TLS Certificates
As covered earlier, certificate issues can lead to ‘505’ errors and other connection failures.
Carefully re-verify that your certificates are validly issued, unexpired, and properly installed on the server. Test the site with HTTPS enabled to uncover any SSL/TLS handshake failures.
Compare Client and Server HTTP Versions
Determine the specific HTTP version supported by the server, and compare it to the browsers/devices exhibiting ‘505’ issues. This reveals any version mismatch.
You can update the server or encourage clients to upgrade their browsers based on the version conflict root cause.
Engage Your Hosting Provider
If you are still unable to determine the cause from server logs and internal troubleshooting, reach out to your hosting provider’s technical support team.
They can help diagnose server-side causes like outdated configurations, depleted resources, or other issues that may be triggering ‘505’ errors.
Maintaining a fully accessible website is essential in today’s digital landscape. The opaque ‘505 HTTP Version Not Supported’ error can bring things grinding to a halt if not properly prevented and addressed.
By learning what causes these errors, implementing preventative best practices, and having a troubleshooting plan, you can adeptly avoid or resolve any ‘505’ issues. Staying ahead of the curve when it comes to protocols and technical challenges will keep your online presence running smoothly.