How to Fix “SSL Handshake Failed” or “Cloudflare 525” Error?

When the error message “SSL Handshake Failed” often also shown as “Cloudflare 525” is displayed on the screen, the majority of users may be unfamiliar with it. However, the name itself provides a clue as to what the issue may be.

In real life, we often shake hands when finalizing an agreement with someone. The same concept applies to SSL certificates – the SSL handshake is a process that occurs between the user’s device and the web server to establish a secure connection.

Installing an SSL certificate on your WordPress site makes sure that it uses HTTPS to establish a secure connection. However, Due to a variety of reasons things can go wrong while establishing this connection between the website’s server and your browser.

But there is nothing to worry about! The good news is that there are several solutions that you can try to fix it.

In this article, I will guide you through a step-by-step process to resolve the “SSL Handshake Failed” error and get you back to browsing the web safely and securely. Let us get started!

Read: 🚩 What Is SSL? and Everything You Need To Know about it

What is SSL handshake mean?

SSL handshake Failed Error message
SSL handshake Failed Error message

SSL Handshake is a process that happens when you try to access websites using HTTPS. It follows a security protocol establishing a secure connection between your website’s server and the browser.

During this process, the browser and the server exchange a series of messages to agree on a set of encryption rules and generate a unique session key.

When the session key is generated, it is then used to encrypt all the data which is going to be transmitted between the browser and the server.

The handshaking process is crucial because it enables the encryption of data, preventing hackers from intercepting and stealing your sensitive information from the website.

Read: 🚩 The Importance of Protecting Your Sensitive Information

You might also notice that the SSL Handshake failed error message has variations depending on the client application or the server you trying to communicate.

For example, if you are using Cloudflare, the SSL handshake Failed error may appear like this.

Error 525 or SSL handshake Failed error
Error 525 or SSL handshake Failed error

What are the reasons that cause SSL handshake Failed message?

Now that you have learned what an SSL handshake is, you may encounter an error message that says “SSL handshake failed.” This message indicates that your browser and the server were unable to establish a secure connection to communicate with each other.

There can be multiple reasons for SSL handshake failure, whether it occurs on the client side or the server side. However, some of the most common reasons are listed below:

The Client side Causes:

Incorrect system time: If the date, time, or timezone on the device is incorrect, SSL certificates may appear invalid, causing the handshake to fail.

Firewall or proxy interference: Firewalls and proxies may block SSL connections or interfere with the SSL handshake, causing it to fail.

Browser Issues: An outdated browser, may cause the SSL handshake to fail.

Network connectivity issues: Network connectivity issues, such as a weak or unstable internet connection, may cause the SSL handshake to fail.

The Server Side Causes:

Invalid SSL certificate: If the SSL certificate is expired, self-signed, or not issued by a trusted certificate authority, the SSL handshake may fail.

Incompatible SSL/TLS versions: If the client and server cannot agree on a common SSL/TLS version, the handshake may fail.

Server configuration issues: If the server’s SSL configuration is incorrect, the handshake may fail. This can include issues with the cipher suite, protocols, or certificate chain.

How to Fix SSL Handshake Failed or Cloudflare 525 Error?

As we mentioned earlier, there can be many reasons that could cause an SSL Handshake Failed error. Therefore, it would be challenging to determine how you should proceed to fix the SSL Handshake Failed error.

However, it doesn’t mean that you cannot take any action. There are several methods you can try to identify the potential main cause of the SSL Handshake Failed error and fix them step by step.

Here are the best methods you can try to fix the SSL Handshake Failed error.

1. Check the system date and time and update them

This is one of the easiest methods that nobody would expect to cause an SSL Handshake Failed error. If your PC’s date and time aren’t well synchronized with the real-time or configured incorrectly, it can cause SSL Handshake Failed error.

An incorrect system time and date can disrupt the SSL handshake if your PC’s or system’s date and time differ from the present or real-time. This is because SSL certificates come with a validity period and exceeding the expiry date will result in an invalid certificate issue.

2. Try on Alternate Browsers

It is also possible that the browser you are using to access the website has some issues. This could be due to your browser settings, a faulty plugin installation, or any other factor. Therefore, to check whether your browser is causing the issue, try switching to an alternate browser.

Let’s suppose that you’re using Google Chrome to access a website and encounter an SSL handshake failed error. However, the same website works fine in an alternative browser, such as Firefox or Brave.

In this case, you can try to reset Google Chrome or whatever browser you were using to its default settings and remove all the installed plugins or extensions.

Afterward, try to connect to your website and enable plugins or extensions one by one to check whether you can connect to the website. This way, you will be able to figure out the exact issue with your browser and fix it.

3. Check your SSL certificate Authenticity and Validity

SSL certificates come with a finite validity period or expiration date to ensure that the validation information remains authentic and accurate. Any issue with the validity information or the exceeding expiry date, the browser will detect will not perform Handshake with the server.

Typically, websites have a validity period of 6 to 12 months for SSL certificates. If it has been past the validity date since you installed the SSL certificate on your website, then it is time to renew or purchase a new SSL license.

One of the easiest methods to check your website’s SSL certificate validity is to use an online tool SSL Checker by Qaulys.

2 How to Fix "SSL Handshake Failed" or "Cloudflare 525" Error?
SSL Server Test

This tool is trusted, reliable, and completely Free to use. The only thing you need to do is to enter your Website’s URL into the “Hostname” section and click on the “Submit” button.

The tool checks your website’s SSL certificates, analyzes them, and shows you the results.

4. Check your browser with the latest SSL protocol

As we have already mentioned, an SSL handshake failure can happen due to multiple reasons. The only effective way to fix this issue is by eliminating the possible causes. And one of the most common reasons for this error is Browser misconfiguration.

We have also suggested that you try connecting to the website using alternate browsers and disabling plugins, but this may not always resolve the issue. There may be browser-related problems that can trigger an SSL Handshake Failure error due to protocol mismatch.

To understand this, consider an example: if the browser you are using only supports TLS 1.1, but your server supports the latest versions of TLS 1.2 and 1.3, then no connection can be established and the result will be an SSL Handshake Failure error.

In this case, you need to update your browser to the latest available version. The new updates generally enable the latest TLS released. However, if it is updated, there are certain things you need to take care of. You must ensure that your browser is properly configured to support the latest TLS version.

To verify this, you can take the help of the same SSL checker tool “Qualys“.

Step 1: Go to by Qualys.

Step 2: Go to the projects tab.

image 2 How to Fix "SSL Handshake Failed" or "Cloudflare 525" Error?

Step 3: Click on the SSL client test link.

Step 4: In the ‘Protocol Support’ section, a message will appear telling you whether your browser supports the latest version of TLS or not.

5. Check whether the server and browser support the Cipher suites or not.

Another common reason for getting an SSL handshake failed error is if the client and the server are not following the same Cipher suites or have a Cipher suit mismatch issue.

What is a Cipher suite?

Cipher suites are sets of cryptographic algorithms used to secure network connections. They include encryption, message authentication, and key exchange methods negotiated during SSL/TLS handshake to establish secure connections between a client and server.

You can compare the cipher suites for the both Client and the server, using the same SSL checker tool by Qualys. To do this all you need to do is,

Step 1: Go to and Click on Project Tabs.

Step 2: Click on SSL client test.

Step 3: You will be provided with a complete list under the Cipher Suits section.

Step 4: Now, the next thing you need to do is to Open a new tab > Open > Click on Project Tabs.

Step 5: Now Click on the SSL Server Test link.

Step 6: Type the Website domain name you were trying to visit and showed the SSL handshake failed error. Followed by clicking on the submit button.

Step 7: Scroll down to see a complete list of Cipher suits the server supports.

Cipher Suites section in a Qualys SSL report
Cipher Suites section in a Qualys SSL report

Now you have to check and verify whether your browser and the server support the same cipher suit or not.

6. Check whether the server is properly configured to Support SNI or not.

An SSL handshake failure error can also be triggered due to misconfigured SNI (Server Name Indication).

An SNI (Server Name Indication) is a TLS protocol extension that enables multiple domains to be served over HTTPS from a single IP address. It works by identifying the requested website’s hostname during the TLS handshake, allowing the server to present the appropriate SSL/TLS certificate.

Each website hosted on a server has its own SSL certificates. But if SNI is not enabled on the server, it can result in an SSL handshake Failed error. It is because the server won’t be able to determine the right certificates.

You can check whether the server has SNI enabled or not by the following two methods:

Checking if a server is using SNI with the help of the SSL checker tool by Qualys

Just like the steps you followed in the above sections, i.e open > Input your domain > click on Submit button.

Summary result section of Qualys SSL checker tool
Summary result section of Qualys SSL checker tool

On the result page, you will find a grade is provided along with the message “This site works only in browsers with SNI support” at the bottom.

Checking if a server is using SNI with the help of the OpenSSL toolkit

1. Open a command prompt or terminal window.

2. Type the following command: openssl s_client -connect servername:443 -servername domainname

Note: Replace “servername” with the name of the server you want to test and “domainname” with the name of the domain you want to test.

3. Press Enter to run the command.

If SNI is enabled, you should see the SSL/TLS certificate details for the domain you specified. If SNI is not enabled, you may see the certificate details for the default domain on the server.

If the command fails to connect, it could be due to a firewall or other network issues, or the server may not support SNI. In such cases, you should contact the server administrator for assistance.


The SSL handshake is an essential process for securing website connections and protecting sensitive information. A failed SSL handshake can cause connection issues and leave your website vulnerable to attacks.

By understanding the causes and symptoms of SSL handshake errors and implementing the appropriate solutions, you can ensure a secure and reliable website connection for your users.

Additionally, regular maintenance and updates of SSL certificates are crucial to maintaining website security and avoiding SSL handshake errors. It is important to stay vigilant and proactive in maintaining SSL security to protect your website and its users.

Frequently Asked Questions

What causes an SSL handshake error?

The causes of SSL handshake errors are:
1. Incorrect system time
2. Firewall or proxy interference
3. Browser Issues
4. Network connectivity issues
5. Invalid SSL certificate
6. Incompatible SSL/TLS versions
7. Server configuration issues

What is an SSL handshake failure?

SSL handshake failure is an error that occurs when a browser fails to establish a secure connection with a website. This can happen due to reasons like expired SSL certificates, incorrect system time and date, or server configuration issues.

What is the full form of SSL handshake?

The full form of SSL handshake is “Secure Sockets Layer handshake”. This is the latest technology that helps to ensure in any data transmitted between the web server and browser is encrypted, making it more difficult for unauthorized parties to intercept or steal sensitive information.

Leave a Reply

Your email address will not be published. Required fields are marked *