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Have you ever attempted to access your website and been met with the annoying Cloudflare Error 520? Isn’t that annoying? Everything is good one minute, and then Cloudflare receives an unexpected answer from your server, causing your site to not load. Such an Error Code 520 will have a bad impact on your website’s visitors.

If ignored, this might result in downtime, lost visitors, and even SEO problems. But don’t freak out! The good news is that by determining the underlying cause, the 520 error code can be fixed.

Is it a DNS setup error, a server crash, or a poorly configured firewall? We’ll assist you in solving it. It is your responsibility as a website owner to make sure your site functions correctly at all times. However, users may encounter the message “520 error: Web Server Is Returning an Unknown Error” when attempting to access its content.

Keep reading and exploring to learn how you can fix the Cloudflare error 520 in 2025.

What is 520 Error Code?

The 520 HTTP status code is a typical issue arising when the server of a website fails to respond as intended. This sometimes happens when an unexpected or empty answer is obtained in response to a Cloudflare server connection attempt, a service that speeds and secures website loading.

Simply put, you get an error message rather than the page loading because the website’s server isn’t providing Cloudflare with the information it requires. Numerous factors, such as server overload, incorrectly configured settings, or firewall problems, might cause this.

Consider getting a latte at a coffee shop. The barista simply looks at you in silence rather than bringing you your drink. When Cloudflare reaches out to your server and does not receive the anticipated response, that is what occurs.

This error code 520 Cloudflare only occurs on websites that use Cloudflare’s services. Usually, it indicates a server-side issue. This indicates that something probably needs to be fixed on your end.

What Leads to Error 520 in Cloudflare?

 

The 520 code error appears when the origin web server connects but fails to execute the request. This often happens when a resource, cron job, or application consumes too many server resources, preventing the server from correctly reacting to every inbound request.

Several typical causes for this error include the following:

• The original web server crashes. Either a resource-intensive script executing on the origin server or improper request interpretation might become the reason. As a result, the server cannot fulfill these requests.
• No Cloudflare networking IP addresses have the right to connect to the origin server. It’s possible that non-whitelisted IP addresses are being blocked by your firewall settings. Verify that the IP address of Cloudflare is not one of them.
• Brief periods of inactivity. A connection originates between the client and server using the Transmission Control Protocol (TCP), which enables data exchange. The idle timeout setting for the web server is 300 seconds by default. Thus, the 520 code error happens because of a TCP timeout setting of less than 300 seconds.
• Response headers that are incompatible with Cloudflare. Message between a website server and a client has become possible via HTTP headers. They include information like cookies, the requested page, and the client’s browser.
• For instance, if there are too many cookies, the header size will increase. It will result in faulty or missing response headers if it surpasses Cloudflare’s 16 KB request header size limit. Moreover, it will display error code 520.

Also Read: How To Fix DNS Server Not Responding: Step by Step Guide To Fix

What is the 520 Status Code’s effect on SEO?

Online web crawlers, sometimes known as spiders, are used by the best search engines like Google to examine and index online material. In order for these crawlers to know how to handle a certain page, they anticipate receiving typical HTTP status codes.

Unable To Crawl

A crawler can identify a server-side issue if it sees a 520 HTTP status code on a webpage. The crawler might not be able to access the page’s content at all since the error does not specify exactly what went wrong.

Continual Failure

Search engines may lower their crawling frequency for a website if the 520 errors are common throughout the site or if they continue over time.

The site’s ability to rank highly in search results may suffer as a result of new or updated content being delayed in indexing.

Experience Of The User

Providing a positive user experience for people is just as important as optimizing a website for search engines. Frequent 520 error returns from a website might irritate users and raise bounce rates.

This pattern may be picked up by search engines and interpreted as an indication of a bad user experience, which could further lower search engine ranking.

Decrease In Link Equity

Because search engines are unable to transfer link equity to a page they cannot reach, the “link juice” or equity from other websites that link to a page on your website that is returning a 520 error may be squandered.

Your Site’s Overall Authority May Suffer As A Result

Despite appearing to be a technical server problem, the error code 520 can have both direct and indirect effects on a website or app SEO. Maintaining the best possible search visibility and user experience requires making sure that these problems are kept to a minimum and promptly fixed.

What is A Step-By-Step Strategy To Fixing Error Code 520?

Step 1: Verify The Server’s Status

• Open your SSH terminal or hosting control panel and log in.
• Find any instances where an application crashes or where resources, such as files, scripts, or configuration elements that the server needs but cannot find are missing.
• Navigate to the error log files ( such as Apache’s error_log or Nginx’s error.log).
• Search for items about timeouts, unusual answers, or connection resets.
• Restart services or update software as remedial measures.

Also Read: Error Code 524: A Complete Guide To Troubleshooting

Step 2: Examine The DNS Configuration

• Open the Cloudflare dashboard and navigate to the DNS settings.
• Check that the information supplied by your web hosting provider corresponds to the A and CNAME records.
• Make sure the proxy status has a proper configuration (gray cloud for direct traffic, orange cloud for Cloudflare protection).
• To improve resolution performance, make sure the TTL (Time-To-Live) numbers are properly arranged.

Step 3: Examine The Security And Firewall Configurations

Cloudflare error code 520 can occasionally be caused by firewall and security settings that prevent Cloudflare’s request headers or obstruct inbound requests.

• To make sure Cloudflare’s IP addresses are not blacklisted, check your web server’s firewall rules.
• Make sure that Cloudflare’s requests are not inadvertently interpreted as harmful by security plugins or server-level protection mechanisms.
• To avoid unforeseen blocking, allow Cloudflare IP addresses in your server settings.
• Examine the server’s error logs to see if the error message has a security rule.
• Try temporarily turning off Cloudflare and evaluating the origin server response directly if, after modifying security settings, an odd answer still appears.

Step 4: Empty The Cache And Cookies In Your Browser

When attempting to load the webpage, Cloudflare error 520 may occur because your browser is storing contradictory or out-of-date data.

• Go to the cache tab in your browser’s options.
• Clear the site’s data, cookies, and cache.
• Check whether the problem still occurs by opening a private or incognito web browser
• After the problem has the solved, think about putting caching rules in place to stop mistakes from happening again.

Step 5: Temporarily Disable .htaccess

• Use SSH or FTP to connect to your server.
• Find the root directory’s .htaccess file.
• Change the name to .htaccess_backup.
• Verify that the website loads correctly following this modification.
• Check for configuration errors in the .htaccess rules before restoring if the problem has been fixed.

Step 6: Look For Issues In The Server Logs

Finding the source of the error code 520 on the origin web server might be helped through examining the server’s error logs.

• Look for excessive latency, request failures, or empty responses in the error log.
• Examine HTTP status codes to identify any unusual response headers.
• To determine when the mistake happened, compare the timestamps of incoming inquiries with the logs.
• Optimize your origin server by increasing resources or setting up stronger timeouts if the error description indicates server overload.

Step 7: Use cURL to Test the Server Response

With the cURL tool, verifying the answer of the origin web server to Cloudflare’s inquiries becomes simpler.

• Run the following command inside your terminal:

-I –resolve actualdomain. com using curl: 80: YOUR_SERVER_IP http://actualdomain. com

• Change YOUR_SERVER_IP to the right server IP and [realdomain].com to your real domain name.
• Your web server is probably the problem if you get an HTTP error or no response at all.

Step 8: Check The Origin Server And Pause Cloudflare

• Access your Cloudflare dashboard by logging in.
• Choose Pause Cloudflare on Site from the Overview menu.
• Access the website immediately via its IP address to check if the source server is responding appropriately.
• Investigate the problem on the hosting provider’s end if the error continues.

Step 9: Contact Your Hosting Provider

You can fix the deeper server-level issues with the assistance of your hosting provider.

If you are  using Temok’s web hosting:

• For help examining the server’s error logs, looking for odd answers, and confirming Cloudflare’s request headers, get in touch with Temok’s support staff.
• The professionals at Temok can assist with resource optimization or suggest managed hosting options to enhance performance and dependability if your origin web server is overburdened or improperly configured.
• Verify that Cloudflare IP addresses are not being blocked by your server’s firewall settings and that the HTTP response contains all of its response headers.

Conclusion

Although error code 520 might be a difficult obstacle, it can be completely avoided with the correct strategy. Moreover, you may greatly lesser the likelihood of running into this problem by keeping your software updated, optimizing firewall and DNS settings, and routinely checking the performance of your server. Comment below if you are still facing the 520 code error. Our professional team will help you fix the error as soon as possible.

FAQs (Frequently Asked Questions)

How Do I Fix Error Code 520?

To fix error code 520, you’ll need to examine your server and Cloudflare settings. Moreover, verifying DNS records, modifying firewall settings, and examining server logs are typical fixes.

What Does 520 Mean In Code?

Cloudflare has a link with an error code 520. When the origin server provides anything unexpected, Cloudflare uses it as a catch-all answer.

What Is A 520 Code?

The server-side issue, known as a 520 error, more precisely “Web server returned an unknown error,” is frequently connected to Cloudflare.

What Is The Result Code 520?

It may become the result of certain website technical problems. It may also occur, though, if the website does not get the necessary information from your queries.