err_ssl_server_cert_bad_format usually occurs to the website using a self-signed certificate.

Securing the domain with an SSL certificate is always a good practice.

However, bad SSL configuration breaks the website.

At Bobcares, we often receive requests to fix this error as part of our Server Management Services.

Today, let’s get into this error in detail and see how our Support Engineers fix it easily.

Causes for err_ssl_server_cert_bad_format

The SSL certificate allows a secure connection from the webserver to the web browser.

An error occurs usually for the domain using a Self-signed certificate. This is because the certificate authority does not sign the certificate.

Similarly, after recent updates, some of the browsers denies the self-signed certificate.

This can also occur in Google Analytics when there are mixed contents on the website. Mixed content error shows up when the content on the secured site uses the urls that contain HTTP.

Most of the web browsers gives warning when the site is loading with mixed contents. The same error looks like

How to fix err_ssl_server_cert_bad_format

Recently of our customers was facing err_ssl_server_cert_bad_format error when accessing his website. Let us discuss how our Support Engineers resolved the error.

Self-signed certificate

On accessing the website we found that the customer was using a self-signed certificate.  Chrome usually rejects the self-signed certificate.

To access the domain from the browser we asked the customer to make changes in the browser settings.

From the right corners select Option >> Preferences. Then, Click on Privacy and Under Certificate option.

Next, click Add Exception. Now enter the URL and select Get Certificate.

Check the box Permanently store this exception. Finally, click Confirm Security Exception.

But our Support Engineers do not suggest to use a self-signed certificate. Instead, we can use Let’s Encrypt certificate for the domain.

The Let’s Encrypt certificate is free as well as signed by the certificate authority.

After our suggestion, we installed Let’s Encrypt for his domain.

In Google analytics

Another customer contacted us saying that Google Analytics was not recording all the information and was throwing an error ERR_SSL_SERVER_CERT_BAD_FORMAT.

On analyzing the SSL certificate for the domain. The domain was using Let’s Encrypt and the SSL validity has not expired.

When accessing the domain from the browser the SSL certificate was showing Mixed content error.

To resolve we had to change the source codes in the domain to load from HTTPS instead of HTTP. The easiest option is to use a plugin based on the CMS to change the source code to HTTPS.

There are multiple plugins available to change the source code. However, we do not recommend to use the plugin but it is the easiest option available.

[Stuggling with bad cert format error? Our experts can help you!]

Conclusion

In short, we have discussed the causes of the error err_ssl_server_cert_bad_format. Also, we have discussed how our Support Engineers resolve the error.