How to Fix ERR_SSL_SERVER_CERT_BAD_FORMAT Error? [6 Ways]

Have you ever faced the ERR_SSL_SERVER_CERT_BAD_FORMAT error? If not, let me inform you it’s quite irritating and frustrating. This error mainly occurs in the browser used by 2.65 billion+ people – “Google Chrome.”

The ERR_SSL_SERVER_CERT_BAD_FORMAT error indicates a problem with the website’s – “SSL Certificate.” SSL certificates create a secure tunnel for your browser-server conversations and protect your information in transit and rest from anyone trying to peek in.

Trusted authorities like Certera, Comodo, Sectigo, DigiCert, GeoTrust, etc., usually issue SSL certificates. Browsers recognize and trust such SSL certificates (issued by trusted CAs). However, on some websites, self-signed SSL certificates are installed.

The website’s owners make these SSL certs not issued by a certificate authority after thorough validation. Browsers don’t trust such (self-signed) SSL certificates, and when you access a site that’s using it, you witness the ERR_SSL_SERVER_CERT_BAD_FORMAT error displayed on your screen.

Here’s a crisp answer if you still need clarification about what the ERR_SSL_SERVER_CERT_BAD_FORMAT error is.

What is the ERR_SSL_SERVER_CERT_BAD_FORMAT Error?

The ERR_SSL_SERVER_CERT_BAD_FORMAT error is a browser error that occurs when there’s an issue with a – website’s SSL certificate. The issue indicates that the browser cannot correctly verify or trust the website’s SSL certificate, often because it is self-signed or improperly configured.

What Causes the ERR_SSL_SERVER_CERT_BAD_FORMAT Error?

Apart from the use of a self-signed SSL certificate, the ERR_SSL_SERVER_CERT_BAD_FORMAT error can occur due to “n” number of other reasons. Here are some of those:

• Incorrect System Date and Time
• Corrupted SSL State within the Browser
• Outdated Browsers or Operating Systems
• Cache Memory and Browsing Data, etc.

How to Fix the ERR_SSL_SERVER_CERT_BAD_FORMAT Error?

Here are the methods that you can use to fix the issue:

• Install SSL from a reputed Certificate Authority
• Add the website to the trusted site’s security zone
• Correct your system’s date and time settings
• Use Google Chrome Properties
• Clear SSL State Cache
• Update browsers and operating systems

Let’s explore each method in depth.

Method 1: Install SSL from a Reputed Certificate Authority

A valid SSL certificate from a recognized Certificate Authority like Certera, Sectigo, DigiCert, or GeoTrust is essential for establishing trust. Browsers trust such SSL certificates instead of self-signed ones.

Before installing one, purchase an SSL cert from a reputable, trusted CA. Once bought, create a Certificate Signing Request and submit it to the CA for validation. Once the CA validates the request and verifies that all the details are – correct and updated, it issues the SSL certificate within minutes or days, depending on the validation level. The CA will send the SSL cert to the registered email ID.

All that’s left now is to download and install the – .ca bundle file, .crt file, and private key on your server. Installing steps vary depending on the server.

Note: This method is only for website owners.

Method 2: Add the Website to the Trusted Site’s Security Zone

Sometimes, adding your website to your browser’s list of trusted sites can resolve SSL errors. This tells your browser to trust the site explicitly. Follow the steps mentioned below to accomplish the same:

• Click Search, placed on the taskbar.
• Type Internet Options and press Enter.
• The Internet Properties window will appear.
• Click on the Security tab.
• Under the Select a zone to view or change security settings section, click the Trusted Sites option.
• Click Sites.
• The Trusted sites window will appear.
• In the Add this website to the zone box, type the URL on which you are getting the ERR_SSL_SERVER_CERT_BAD_FORMAT error.
• Click Add.
• Click Close.
• Try re-accessing the website.

Method 3: Correct Your System’s Date and Time Settings

Ensure the date and time on your device are correct, as an incorrect system time can cause HTTPS traffic to fail and trigger the error in discussion.

Follow the steps given below to update the date and time:

• Click Search, placed on the taskbar.
• Type Date & time settings and press Enter.
• The Settings window will appear.
• Toggle the switch on against the Set time automatically option.
• Toggle the switch on against the Set time zone automatically option.
• Try re-accessing the site.

Method 4: Use Google Chrome Properties

Modifying Google Chrome’s properties can sometimes bypass SSL errors, including the one in question. But this should be done with – “caution,” as it can compromise security. Follow these steps:

• Open a fresh tab in Google Chrome.
• Click the Customize and control Google Chrome icon (three vertical dots).
• From the list, click Settings.
• The Settings window will appear.
• In the left pane, click System.
• In the right pane, click the Open your computer’s proxy settings option.
• The Network & Internet window will appear.
• Under the Advanced Network Settings section, click Network and Sharing Center.
• The Network and Sharing Center window will appear.
• Click Internet Options.
• Click on the Security tab.
• Under the Select a zone to view or change security settings section, click the Trusted Sites option.
• Click Sites.
• The Trusted sites window will appear.
• In the Add this website to the zone box, type the URL on which you are getting the ERR_SSL_SERVER_CERT_BAD_FORMAT error.
• Click Add.
• Click Close.
• Re-access the site.

Method 5: Clear SSL State Cache

Browsers tend to cache SSL certificates to expedite page loading. But sometimes, because of these cached SSL certificate data, the browser cannot fetch the updated certificates, resulting in an ERR_SSL_SERVER_CERT_BAD_FORMAT error.

Follow the steps mentioned below to clear the browser’s SSL State cache:

• Click Search, placed on the taskbar.
• Type Internet Options and press Enter.
• The Internet Properties window will appear.
• Navigate to the Content tab.
• Under the Certificates section, click the Clear SSL Slate button.

Method 6: Update Browsers and Operating Systems

Older versions might not support newer SSL protocols and lead to mismatches. These mismatches ultimately lead to the ERR_SSL_SERVER_CERT_BAD_FORMAT error. Therefore, regularly update the OS and browser. Follow the steps mentioned below to update both of these:

Here’s how to update your browser:

• Open a fresh tab in Chrome.
• Click on Customize and control Google Chrome icon (three vertical dots).
• From the list, select Help, and click About Google Chrome.
• The update will start automatically. It will only happen if you are not using the – latest version.

Here’s how to update your Operating System:

• Click Search placed on the taskbar.
• Type Windows Update settings and press Enter.
• The Settings window will appear.
• Click on the Check for updates button.
• Once it’s updated, re-access the site.

Conclusion

Several effective strategies exist to fix the – “ERR_SSL_SERVER_CERT_BAD_FORMAT” issue, from installing SSL certs from trusted certificate authorities to updating your browser and operating system. Remember, keeping your system’s date and time accurate, clearing the SSL state cache, and adding websites to trusted zones can also help.